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Mortality and Readmission Correlations
The Centers for Medicare & Medicaid Services (CMS) publicly reports hospital‐specific, 30‐day risk‐standardized mortality and readmission rates for Medicare fee‐for‐service patients admitted with acute myocardial infarction (AMI), heart failure (HF), and pneumonia.1 These measures are intended to reflect hospital performance on quality of care provided to patients during and after hospitalization.2, 3
Quality‐of‐care measures for a given disease are often assumed to reflect the quality of care for that particular condition. However, studies have found limited association between condition‐specific process measures and either mortality or readmission rates for those conditions.46 Mortality and readmission rates may instead reflect broader hospital‐wide or specialty‐wide structure, culture, and practice. For example, studies have previously found that hospitals differ in mortality or readmission rates according to organizational structure,7 financial structure,8 culture,9, 10 information technology,11 patient volume,1214 academic status,12 and other institution‐wide factors.12 There is now a strong policy push towards developing hospital‐wide (all‐condition) measures, beginning with readmission.15
It is not clear how much of the quality of care for a given condition is attributable to hospital‐wide influences that affect all conditions rather than disease‐specific factors. If readmission or mortality performance for a particular condition reflects, in large part, broader institutional characteristics, then improvement efforts might better be focused on hospital‐wide activities, such as team training or implementing electronic medical records. On the other hand, if the disease‐specific measures reflect quality strictly for those conditions, then improvement efforts would be better focused on disease‐specific care, such as early identification of the relevant patient population or standardizing disease‐specific care. As hospitals work to improve performance across an increasingly wide variety of conditions, it is becoming more important for hospitals to prioritize and focus their activities effectively and efficiently.
One means of determining the relative contribution of hospital versus disease factors is to explore whether outcome rates are consistent among different conditions cared for in the same hospital. If mortality (or readmission) rates across different conditions are highly correlated, it would suggest that hospital‐wide factors may play a substantive role in outcomes. Some studies have found that mortality for a particular surgical condition is a useful proxy for mortality for other surgical conditions,16, 17 while other studies have found little correlation among mortality rates for various medical conditions.18, 19 It is also possible that correlation varies according to hospital characteristics; for example, smaller or nonteaching hospitals might be more homogenous in their care than larger, less homogeneous institutions. No studies have been performed using publicly reported estimates of risk‐standardized mortality or readmission rates. In this study we use the publicly reported measures of 30‐day mortality and 30‐day readmission for AMI, HF, and pneumonia to examine whether, and to what degree, mortality rates track together within US hospitals, and separately, to what degree readmission rates track together within US hospitals.
METHODS
Data Sources
CMS calculates risk‐standardized mortality and readmission rates, and patient volume, for all acute care nonfederal hospitals with one or more eligible case of AMI, HF, and pneumonia annually based on fee‐for‐service (FFS) Medicare claims. CMS publicly releases the rates for the large subset of hospitals that participate in public reporting and have 25 or more cases for the conditions over the 3‐year period between July 2006 and June 2009. We estimated the rates for all hospitals included in the measure calculations, including those with fewer than 25 cases, using the CMS methodology and data obtained from CMS. The distribution of these rates has been previously reported.20, 21 In addition, we used the 2008 American Hospital Association (AHA) Survey to obtain data about hospital characteristics, including number of beds, hospital ownership (government, not‐for‐profit, for‐profit), teaching status (member of Council of Teaching Hospitals, other teaching hospital, nonteaching), presence of specialized cardiac capabilities (coronary artery bypass graft surgery, cardiac catheterization lab without cardiac surgery, neither), US Census Bureau core‐based statistical area (division [subarea of area with urban center >2.5 million people], metropolitan [urban center of at least 50,000 people], micropolitan [urban center of between 10,000 and 50,000 people], and rural [<10,000 people]), and safety net status22 (yes/no). Safety net status was defined as either public hospitals or private hospitals with a Medicaid caseload greater than one standard deviation above their respective state's mean private hospital Medicaid caseload using the 2007 AHA Annual Survey data.
Study Sample
This study includes 2 hospital cohorts, 1 for mortality and 1 for readmission. Hospitals were eligible for the mortality cohort if the dataset included risk‐standardized mortality rates for all 3 conditions (AMI, HF, and pneumonia). Hospitals were eligible for the readmission cohort if the dataset included risk‐standardized readmission rates for all 3 of these conditions.
Risk‐Standardized Measures
The measures include all FFS Medicare patients who are 65 years old, have been enrolled in FFS Medicare for the 12 months before the index hospitalization, are admitted with 1 of the 3 qualifying diagnoses, and do not leave the hospital against medical advice. The mortality measures include all deaths within 30 days of admission, and all deaths are attributable to the initial admitting hospital, even if the patient is then transferred to another acute care facility. Therefore, for a given hospital, transfers into the hospital are excluded from its rate, but transfers out are included. The readmission measures include all readmissions within 30 days of discharge, and all readmissions are attributable to the final discharging hospital, even if the patient was originally admitted to a different acute care facility. Therefore, for a given hospital, transfers in are included in its rate, but transfers out are excluded. For mortality measures, only 1 hospitalization for a patient in a specific year is randomly selected if the patient has multiple hospitalizations in the year. For readmission measures, admissions in which the patient died prior to discharge, and admissions within 30 days of an index admission, are not counted as index admissions.
Outcomes for all measures are all‐cause; however, for the AMI readmission measure, planned admissions for cardiac procedures are not counted as readmissions. Patients in observation status or in non‐acute care facilities are not counted as readmissions. Detailed specifications for the outcomes measures are available at the National Quality Measures Clearinghouse.23
The derivation and validation of the risk‐standardized outcome measures have been previously reported.20, 21, 2327 The measures are derived from hierarchical logistic regression models that include age, sex, clinical covariates, and a hospital‐specific random effect. The rates are calculated as the ratio of the number of predicted outcomes (obtained from a model applying the hospital‐specific effect) to the number of expected outcomes (obtained from a model applying the average effect among hospitals), multiplied by the unadjusted overall 30‐day rate.
Statistical Analysis
We examined patterns and distributions of hospital volume, risk‐standardized mortality rates, and risk‐standardized readmission rates among included hospitals. To measure the degree of association among hospitals' risk‐standardized mortality rates for AMI, HF, and pneumonia, we calculated Pearson correlation coefficients, resulting in 3 correlations for the 3 pairs of conditions (AMI and HF, AMI and pneumonia, HF and pneumonia), and tested whether they were significantly different from 0. We also conducted a factor analysis using the principal component method with a minimum eigenvalue of 1 to retain factors to determine whether there was a single common factor underlying mortality performance for the 3 conditions.28 Finally, we divided hospitals into quartiles of performance for each outcome based on the point estimate of risk‐standardized rate, and compared quartile of performance between condition pairs for each outcome. For each condition pair, we assessed the percent of hospitals in the same quartile of performance in both conditions, the percent of hospitals in either the top quartile of performance or the bottom quartile of performance for both, and the percent of hospitals in the top quartile for one and the bottom quartile for the other. We calculated the weighted kappa for agreement on quartile of performance between condition pairs for each outcome and the Spearman correlation for quartiles of performance. Then, we examined Pearson correlation coefficients in different subgroups of hospitals, including by size, ownership, teaching status, cardiac procedure capability, statistical area, and safety net status. In order to determine whether these correlations differed by hospital characteristics, we tested if the Pearson correlation coefficients were different between any 2 subgroups using the method proposed by Fisher.29 We repeated all of these analyses separately for the risk‐standardized readmission rates.
To determine whether correlations between mortality rates were significantly different than correlations between readmission rates for any given condition pair, we used the method recommended by Raghunathan et al.30 For these analyses, we included only hospitals reporting both mortality and readmission rates for the condition pairs. We used the same methods to determine whether correlations between mortality rates were significantly different than correlations between readmission rates for any given condition pair among subgroups of hospital characteristics.
All analyses and graphing were performed using the SAS statistical package version 9.2 (SAS Institute, Cary, NC). We considered a P‐value < 0.05 to be statistically significant, and all statistical tests were 2‐tailed.
RESULTS
The mortality cohort included 4559 hospitals, and the readmission cohort included 4468 hospitals. The majority of hospitals was small, nonteaching, and did not have advanced cardiac capabilities such as cardiac surgery or cardiac catheterization (Table 1).
Description | Mortality Measures | Readmission Measures |
---|---|---|
Hospital N = 4559 | Hospital N = 4468 | |
N (%)* | N (%)* | |
| ||
No. of beds | ||
>600 | 157 (3.4) | 156 (3.5) |
300600 | 628 (13.8) | 626 (14.0) |
<300 | 3588 (78.7) | 3505 (78.5) |
Unknown | 186 (4.08) | 181 (4.1) |
Mean (SD) | 173.24 (189.52) | 175.23 (190.00) |
Ownership | ||
Not‐for‐profit | 2650 (58.1) | 2619 (58.6) |
For‐profit | 672 (14.7) | 663 (14.8) |
Government | 1051 (23.1) | 1005 (22.5) |
Unknown | 186 (4.1) | 181 (4.1) |
Teaching status | ||
COTH | 277 (6.1) | 276 (6.2) |
Teaching | 505 (11.1) | 503 (11.3) |
Nonteaching | 3591 (78.8) | 3508 (78.5) |
Unknown | 186 (4.1) | 181 (4.1) |
Cardiac facility type | ||
CABG | 1471 (32.3) | 1467 (32.8) |
Cath lab | 578 (12.7) | 578 (12.9) |
Neither | 2324 (51.0) | 2242 (50.2) |
Unknown | 186 (4.1) | 181 (4.1) |
Core‐based statistical area | ||
Division | 621 (13.6) | 618 (13.8) |
Metro | 1850 (40.6) | 1835 (41.1) |
Micro | 801 (17.6) | 788 (17.6) |
Rural | 1101 (24.2) | 1046 (23.4) |
Unknown | 186 (4.1) | 181 (4.1) |
Safety net status | ||
No | 2995 (65.7) | 2967 (66.4) |
Yes | 1377 (30.2) | 1319 (29.5) |
Unknown | 187 (4.1) | 182 (4.1) |
For mortality measures, the smallest median number of cases per hospital was for AMI (48; interquartile range [IQR], 13,171), and the greatest number was for pneumonia (178; IQR, 87, 336). The same pattern held for readmission measures (AMI median 33; IQR; 9, 150; pneumonia median 191; IQR, 95, 352.5). With respect to mortality measures, AMI had the highest rate and HF the lowest rate; however, for readmission measures, HF had the highest rate and pneumonia the lowest rate (Table 2).
Description | Mortality Measures (N = 4559) | Readmission Measures (N = 4468) | ||||
---|---|---|---|---|---|---|
AMI | HF | PN | AMI | HF | PN | |
| ||||||
Total discharges | 558,653 | 1,094,960 | 1,114,706 | 546,514 | 1,314,394 | 1,152,708 |
Hospital volume | ||||||
Mean (SD) | 122.54 (172.52) | 240.18 (271.35) | 244.51 (220.74) | 122.32 (201.78) | 294.18 (333.2) | 257.99 (228.5) |
Median (IQR) | 48 (13, 171) | 142 (56, 337) | 178 (87, 336) | 33 (9, 150) | 172.5 (68, 407) | 191 (95, 352.5) |
Range min, max | 1, 1379 | 1, 2814 | 1, 2241 | 1, 1611 | 1, 3410 | 2, 2359 |
30‐Day risk‐standardized rate* | ||||||
Mean (SD) | 15.7 (1.8) | 10.9 (1.6) | 11.5 (1.9) | 19.9 (1.5) | 24.8 (2.1) | 18.5 (1.7) |
Median (IQR) | 15.7 (14.5, 16.8) | 10.8 (9.9, 11.9) | 11.3 (10.2, 12.6) | 19.9 (18.9, 20.8) | 24.7 (23.4, 26.1) | 18.4 (17.3, 19.5) |
Range min, max | 10.3, 24.6 | 6.6, 18.2 | 6.7, 20.9 | 15.2, 26.3 | 17.3, 32.4 | 13.6, 26.7 |
Every mortality measure was significantly correlated with every other mortality measure (range of correlation coefficients, 0.270.41, P < 0.0001 for all 3 correlations). For example, the correlation between risk‐standardized mortality rates (RSMR) for HF and pneumonia was 0.41. Similarly, every readmission measure was significantly correlated with every other readmission measure (range of correlation coefficients, 0.320.47; P < 0.0001 for all 3 correlations). Overall, the lowest correlation was between risk‐standardized mortality rates for AMI and pneumonia (r = 0.27), and the highest correlation was between risk‐standardized readmission rates (RSRR) for HF and pneumonia (r = 0.47) (Table 3).
Description | Mortality Measures | Readmission Measures | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
N | AMI and HF | AMI and PN | HF and PN | AMI and HF | AMI and PN | HF and PN | ||||||||
r | P | r | P | r | P | N | r | P | r | P | r | P | ||
| ||||||||||||||
All | 4559 | 0.30 | 0.27 | 0.41 | 4468 | 0.38 | 0.32 | 0.47 | ||||||
Hospitals with 25 patients | 2872 | 0.33 | 0.30 | 0.44 | 2467 | 0.44 | 0.38 | 0.51 | ||||||
No. of beds | 0.15 | 0.005 | 0.0009 | <0.0001 | <0.0001 | <0.0001 | ||||||||
>600 | 157 | 0.38 | 0.43 | 0.51 | 156 | 0.67 | 0.50 | 0.66 | ||||||
300600 | 628 | 0.29 | 0.30 | 0.49 | 626 | 0.54 | 0.45 | 0.58 | ||||||
<300 | 3588 | 0.27 | 0.23 | 0.37 | 3505 | 0.30 | 0.26 | 0.44 | ||||||
Ownership | 0.021 | 0.05 | 0.39 | 0.0004 | 0.0004 | 0.003 | ||||||||
Not‐for‐profit | 2650 | 0.32 | 0.28 | 0.42 | 2619 | 0.43 | 0.36 | 0.50 | ||||||
For‐profit | 672 | 0.30 | 0.23 | 0.40 | 663 | 0.29 | 0.22 | 0.40 | ||||||
Government | 1051 | 0.24 | 0.22 | 0.39 | 1005 | 0.32 | 0.29 | 0.45 | ||||||
Teaching status | 0.11 | 0.08 | 0.0012 | <0.0001 | 0.0002 | 0.0003 | ||||||||
COTH | 277 | 0.31 | 0.34 | 0.54 | 276 | 0.54 | 0.47 | 0.59 | ||||||
Teaching | 505 | 0.22 | 0.28 | 0.43 | 503 | 0.52 | 0.42 | 0.56 | ||||||
Nonteaching | 3591 | 0.29 | 0.24 | 0.39 | 3508 | 0.32 | 0.26 | 0.44 | ||||||
Cardiac facility type | 0.022 | 0.006 | <0.0001 | <0.0001 | 0.0006 | 0.004 | ||||||||
CABG | 1471 | 0.33 | 0.29 | 0.47 | 1467 | 0.48 | 0.37 | 0.52 | ||||||
Cath lab | 578 | 0.25 | 0.26 | 0.36 | 578 | 0.32 | 0.37 | 0.47 | ||||||
Neither | 2324 | 0.26 | 0.21 | 0.36 | 2242 | 0.28 | 0.27 | 0.44 | ||||||
Core‐based statistical area | 0.0001 | <0.0001 | 0.002 | <0.0001 | <0.0001 | <0.0001 | ||||||||
Division | 621 | 0.38 | 0.34 | 0.41 | 618 | 0.46 | 0.40 | 0.56 | ||||||
Metro | 1850 | 0.26 | 0.26 | 0.42 | 1835 | 0.38 | 0.30 | 0.40 | ||||||
Micro | 801 | 0.23 | 0.22 | 0.34 | 788 | 0.32 | 0.30 | 0.47 | ||||||
Rural | 1101 | 0.21 | 0.13 | 0.32 | 1046 | 0.22 | 0.21 | 0.44 | ||||||
Safety net status | 0.001 | 0.027 | 0.68 | 0.029 | 0.037 | 0.28 | ||||||||
No | 2995 | 0.33 | 0.28 | 0.41 | 2967 | 0.40 | 0.33 | 0.48 | ||||||
Yes | 1377 | 0.23 | 0.21 | 0.40 | 1319 | 0.34 | 0.30 | 0.45 |
Both the factor analysis for the mortality measures and the factor analysis for the readmission measures yielded only one factor with an eigenvalue >1. In each factor analysis, this single common factor kept more than half of the data based on the cumulative eigenvalue (55% for mortality measures and 60% for readmission measures). For the mortality measures, the pattern of RSMR for myocardial infarction (MI), heart failure (HF), and pneumonia (PN) in the factor was high (0.68 for MI, 0.78 for HF, and 0.76 for PN); the same was true of the RSRR in the readmission measures (0.72 for MI, 0.81 for HF, and 0.78 for PN).
For all condition pairs and both outcomes, a third or more of hospitals were in the same quartile of performance for both conditions of the pair (Table 4). Hospitals were more likely to be in the same quartile of performance if they were in the top or bottom quartile than if they were in the middle. Less than 10% of hospitals were in the top quartile for one condition in the mortality or readmission pair and in the bottom quartile for the other condition in the pair. Kappa scores for same quartile of performance between pairs of outcomes ranged from 0.16 to 0.27, and were highest for HF and pneumonia for both mortality and readmission rates.
Condition Pair | Same Quartile (Any) (%) | Same Quartile (Q1 or Q4) (%) | Q1 in One and Q4 in Another (%) | Weighted Kappa | Spearman Correlation |
---|---|---|---|---|---|
| |||||
Mortality | |||||
MI and HF | 34.8 | 20.2 | 7.9 | 0.19 | 0.25 |
MI and PN | 32.7 | 18.8 | 8.2 | 0.16 | 0.22 |
HF and PN | 35.9 | 21.8 | 5.0 | 0.26 | 0.36 |
Readmission | |||||
MI and HF | 36.6 | 21.0 | 7.5 | 0.22 | 0.28 |
MI and PN | 34.0 | 19.6 | 8.1 | 0.19 | 0.24 |
HF and PN | 37.1 | 22.6 | 5.4 | 0.27 | 0.37 |
In subgroup analyses, the highest mortality correlation was between HF and pneumonia in hospitals with more than 600 beds (r = 0.51, P = 0.0009), and the highest readmission correlation was between AMI and HF in hospitals with more than 600 beds (r = 0.67, P < 0.0001). Across both measures and all 3 condition pairs, correlations between conditions increased with increasing hospital bed size, presence of cardiac surgery capability, and increasing population of the hospital's Census Bureau statistical area. Furthermore, for most measures and condition pairs, correlations between conditions were highest in not‐for‐profit hospitals, hospitals belonging to the Council of Teaching Hospitals, and non‐safety net hospitals (Table 3).
For all condition pairs, the correlation between readmission rates was significantly higher than the correlation between mortality rates (P < 0.01). In subgroup analyses, readmission correlations were also significantly higher than mortality correlations for all pairs of conditions among moderate‐sized hospitals, among nonprofit hospitals, among teaching hospitals that did not belong to the Council of Teaching Hospitals, and among non‐safety net hospitals (Table 5).
Description | AMI and HF | AMI and PN | HF and PN | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
N | MC | RC | P | N | MC | RC | P | N | MC | RC | P | |
| ||||||||||||
All | 4457 | 0.31 | 0.38 | <0.0001 | 4459 | 0.27 | 0.32 | 0.007 | 4731 | 0.41 | 0.46 | 0.0004 |
Hospitals with 25 patients | 2472 | 0.33 | 0.44 | <0.001 | 2463 | 0.31 | 0.38 | 0.01 | 4104 | 0.42 | 0.47 | 0.001 |
No. of beds | ||||||||||||
>600 | 156 | 0.38 | 0.67 | 0.0002 | 156 | 0.43 | 0.50 | 0.48 | 160 | 0.51 | 0.66 | 0.042 |
300600 | 626 | 0.29 | 0.54 | <0.0001 | 626 | 0.31 | 0.45 | 0.003 | 630 | 0.49 | 0.58 | 0.033 |
<300 | 3494 | 0.28 | 0.30 | 0.21 | 3496 | 0.23 | 0.26 | 0.17 | 3733 | 0.37 | 0.43 | 0.003 |
Ownership | ||||||||||||
Not‐for‐profit | 2614 | 0.32 | 0.43 | <0.0001 | 2617 | 0.28 | 0.36 | 0.003 | 2697 | 0.42 | 0.50 | 0.0003 |
For‐profit | 662 | 0.30 | 0.29 | 0.90 | 661 | 0.23 | 0.22 | 0.75 | 699 | 0.40 | 0.40 | 0.99 |
Government | 1000 | 0.25 | 0.32 | 0.09 | 1000 | 0.22 | 0.29 | 0.09 | 1127 | 0.39 | 0.43 | 0.21 |
Teaching status | ||||||||||||
COTH | 276 | 0.31 | 0.54 | 0.001 | 277 | 0.35 | 0.46 | 0.10 | 278 | 0.54 | 0.59 | 0.41 |
Teaching | 504 | 0.22 | 0.52 | <0.0001 | 504 | 0.28 | 0.42 | 0.012 | 508 | 0.43 | 0.56 | 0.005 |
Nonteaching | 3496 | 0.29 | 0.32 | 0.18 | 3497 | 0.24 | 0.26 | 0.46 | 3737 | 0.39 | 0.43 | 0.016 |
Cardiac facility type | ||||||||||||
CABG | 1465 | 0.33 | 0.48 | <0.0001 | 1467 | 0.30 | 0.37 | 0.018 | 1483 | 0.47 | 0.51 | 0.103 |
Cath lab | 577 | 0.25 | 0.32 | 0.18 | 577 | 0.26 | 0.37 | 0.046 | 579 | 0.36 | 0.47 | 0.022 |
Neither | 2234 | 0.26 | 0.28 | 0.48 | 2234 | 0.21 | 0.27 | 0.037 | 2461 | 0.36 | 0.44 | 0.002 |
Core‐based statistical area | ||||||||||||
Division | 618 | 0.38 | 0.46 | 0.09 | 620 | 0.34 | 0.40 | 0.18 | 630 | 0.41 | 0.56 | 0.001 |
Metro | 1833 | 0.26 | 0.38 | <0.0001 | 1832 | 0.26 | 0.30 | 0.21 | 1896 | 0.42 | 0.40 | 0.63 |
Micro | 787 | 0.24 | 0.32 | 0.08 | 787 | 0.22 | 0.30 | 0.11 | 820 | 0.34 | 0.46 | 0.003 |
Rural | 1038 | 0.21 | 0.22 | 0.83 | 1039 | 0.13 | 0.21 | 0.056 | 1177 | 0.32 | 0.43 | 0.002 |
Safety net status | ||||||||||||
No | 2961 | 0.33 | 0.40 | 0.001 | 2963 | 0.28 | 0.33 | 0.036 | 3062 | 0.41 | 0.48 | 0.001 |
Yes | 1314 | 0.23 | 0.34 | 0.003 | 1314 | 0.22 | 0.30 | 0.015 | 1460 | 0.40 | 0.45 | 0.14 |
DISCUSSION
In this study, we found that risk‐standardized mortality rates for 3 common medical conditions were moderately correlated within institutions, as were risk‐standardized readmission rates. Readmission rates were more strongly correlated than mortality rates, and all rates tracked closest together in large, urban, and/or teaching hospitals. Very few hospitals were in the top quartile of performance for one condition and in the bottom quartile for a different condition.
Our findings are consistent with the hypothesis that 30‐day risk‐standardized mortality and 30‐day risk‐standardized readmission rates, in part, capture broad aspects of hospital quality that transcend condition‐specific activities. In this study, readmission rates tracked better together than mortality rates for every pair of conditions, suggesting that there may be a greater contribution of hospital‐wide environment, structure, and processes to readmission rates than to mortality rates. This difference is plausible because services specific to readmission, such as discharge planning, care coordination, medication reconciliation, and discharge communication with patients and outpatient clinicians, are typically hospital‐wide processes.
Our study differs from earlier studies of medical conditions in that the correlations we found were higher.18, 19 There are several possible explanations for this difference. First, during the intervening 1525 years since those studies were performed, care for these conditions has evolved substantially, such that there are now more standardized protocols available for all 3 of these diseases. Hospitals that are sufficiently organized or acculturated to systematically implement care protocols may have the infrastructure or culture to do so for all conditions, increasing correlation of performance among conditions. In addition, there are now more technologies and systems available that span care for multiple conditions, such as electronic medical records and quality committees, than were available in previous generations. Second, one of these studies utilized less robust risk‐adjustment,18 and neither used the same methodology of risk standardization. Nonetheless, it is interesting to note that Rosenthal and colleagues identified the same increase in correlation with higher volumes than we did.19 Studies investigating mortality correlations among surgical procedures, on the other hand, have generally found higher correlations than we found in these medical conditions.16, 17
Accountable care organizations will be assessed using an all‐condition readmission measure,31 several states track all‐condition readmission rates,3234 and several countries measure all‐condition mortality.35 An all‐condition measure for quality assessment first requires that there be a hospital‐wide quality signal above and beyond disease‐specific care. This study suggests that a moderate signal exists for readmission and, to a slightly lesser extent, for mortality, across 3 common conditions. There are other considerations, however, in developing all‐condition measures. There must be adequate risk adjustment for the wide variety of conditions that are included, and there must be a means of accounting for the variation in types of conditions and procedures cared for by different hospitals. Our study does not address these challenges, which have been described to be substantial for mortality measures.35
We were surprised by the finding that risk‐standardized rates correlated more strongly within larger institutions than smaller ones, because one might assume that care within smaller hospitals might be more homogenous. It may be easier, however, to detect a quality signal in hospitals with higher volumes of patients for all 3 conditions, because estimates for these hospitals are more precise. Consequently, we have greater confidence in results for larger volumes, and suspect a similar quality signal may be present but more difficult to detect statistically in smaller hospitals. Overall correlations were higher when we restricted the sample to hospitals with at least 25 cases, as is used for public reporting. It is also possible that the finding is real given that large‐volume hospitals have been demonstrated to provide better care for these conditions and are more likely to adopt systems of care that affect multiple conditions, such as electronic medical records.14, 36
The kappa scores comparing quartile of national performance for pairs of conditions were only in the fair range. There are several possible explanations for this fact: 1) outcomes for these 3 conditions are not measuring the same constructs; 2) they are all measuring the same construct, but they are unreliable in doing so; and/or 3) hospitals have similar latent quality for all 3 conditions, but the national quality of performance differs by condition, yielding variable relative performance per hospital for each condition. Based solely on our findings, we cannot distinguish which, if any, of these explanations may be true.31
Our study has several limitations. First, all 3 conditions currently publicly reported by CMS are medical diagnoses, although AMI patients may be cared for in distinct cardiology units and often undergo procedures; therefore, we cannot determine the degree to which correlations reflect hospital‐wide quality versus medicine‐wide quality. An institution may have a weak medicine department but a strong surgical department or vice versa. Second, it is possible that the correlations among conditions for readmission and among conditions for mortality are attributable to patient characteristics that are not adequately adjusted for in the risk‐adjustment model, such as socioeconomic factors, or to hospital characteristics not related to quality, such as coding practices or inter‐hospital transfer rates. For this to be true, these unmeasured characteristics would have to be consistent across different conditions within each hospital and have a consistent influence on outcomes. Third, it is possible that public reporting may have prompted disease‐specific focus on these conditions. We do not have data from non‐publicly reported conditions to test this hypothesis. Fourth, there are many small‐volume hospitals in this study; their estimates for readmission and mortality are less reliable than for large‐volume hospitals, potentially limiting our ability to detect correlations in this group of hospitals.
This study lends credence to the hypothesis that 30‐day risk‐standardized mortality and readmission rates for individual conditions may reflect aspects of hospital‐wide quality or at least medicine‐wide quality, although the correlations are not large enough to conclude that hospital‐wide factors play a dominant role, and there are other possible explanations for the correlations. Further work is warranted to better understand the causes of the correlations, and to better specify the nature of hospital factors that contribute to correlations among outcomes.
Acknowledgements
Disclosures: Dr Horwitz is supported by the National Institute on Aging (K08 AG038336) and by the American Federation of Aging Research through the Paul B. Beeson Career Development Award Program. Dr Horwitz is also a Pepper Scholar with support from the Claude D. Pepper Older Americans Independence Center at Yale University School of Medicine (P30 AG021342 NIH/NIA). Dr Krumholz is supported by grant U01 HL105270‐01 (Center for Cardiovascular Outcomes Research at Yale University) from the National Heart, Lung, and Blood Institute. Dr Krumholz chairs a cardiac scientific advisory board for UnitedHealth. Authors Drye, Krumholz, and Wang receive support from the Centers for Medicare & Medicaid Services (CMS) to develop and maintain performance measures that are used for public reporting. The analyses upon which this publication is based were performed under Contract Number HHSM‐500‐2008‐0025I Task Order T0001, entitled Measure & Instrument Development and Support (MIDS)Development and Re‐evaluation of the CMS Hospital Outcomes and Efficiency Measures, funded by the Centers for Medicare & Medicaid Services, an agency of the US Department of Health and Human Services. The Centers for Medicare & Medicaid Services reviewed and approved the use of its data for this work, and approved submission of the manuscript. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government. The authors assume full responsibility for the accuracy and completeness of the ideas presented.
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- Hospital inpatient mortality. Is it a predictor of quality?N Engl J Med.1987;317(26):1674–1680. , , , , .
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The Centers for Medicare & Medicaid Services (CMS) publicly reports hospital‐specific, 30‐day risk‐standardized mortality and readmission rates for Medicare fee‐for‐service patients admitted with acute myocardial infarction (AMI), heart failure (HF), and pneumonia.1 These measures are intended to reflect hospital performance on quality of care provided to patients during and after hospitalization.2, 3
Quality‐of‐care measures for a given disease are often assumed to reflect the quality of care for that particular condition. However, studies have found limited association between condition‐specific process measures and either mortality or readmission rates for those conditions.46 Mortality and readmission rates may instead reflect broader hospital‐wide or specialty‐wide structure, culture, and practice. For example, studies have previously found that hospitals differ in mortality or readmission rates according to organizational structure,7 financial structure,8 culture,9, 10 information technology,11 patient volume,1214 academic status,12 and other institution‐wide factors.12 There is now a strong policy push towards developing hospital‐wide (all‐condition) measures, beginning with readmission.15
It is not clear how much of the quality of care for a given condition is attributable to hospital‐wide influences that affect all conditions rather than disease‐specific factors. If readmission or mortality performance for a particular condition reflects, in large part, broader institutional characteristics, then improvement efforts might better be focused on hospital‐wide activities, such as team training or implementing electronic medical records. On the other hand, if the disease‐specific measures reflect quality strictly for those conditions, then improvement efforts would be better focused on disease‐specific care, such as early identification of the relevant patient population or standardizing disease‐specific care. As hospitals work to improve performance across an increasingly wide variety of conditions, it is becoming more important for hospitals to prioritize and focus their activities effectively and efficiently.
One means of determining the relative contribution of hospital versus disease factors is to explore whether outcome rates are consistent among different conditions cared for in the same hospital. If mortality (or readmission) rates across different conditions are highly correlated, it would suggest that hospital‐wide factors may play a substantive role in outcomes. Some studies have found that mortality for a particular surgical condition is a useful proxy for mortality for other surgical conditions,16, 17 while other studies have found little correlation among mortality rates for various medical conditions.18, 19 It is also possible that correlation varies according to hospital characteristics; for example, smaller or nonteaching hospitals might be more homogenous in their care than larger, less homogeneous institutions. No studies have been performed using publicly reported estimates of risk‐standardized mortality or readmission rates. In this study we use the publicly reported measures of 30‐day mortality and 30‐day readmission for AMI, HF, and pneumonia to examine whether, and to what degree, mortality rates track together within US hospitals, and separately, to what degree readmission rates track together within US hospitals.
METHODS
Data Sources
CMS calculates risk‐standardized mortality and readmission rates, and patient volume, for all acute care nonfederal hospitals with one or more eligible case of AMI, HF, and pneumonia annually based on fee‐for‐service (FFS) Medicare claims. CMS publicly releases the rates for the large subset of hospitals that participate in public reporting and have 25 or more cases for the conditions over the 3‐year period between July 2006 and June 2009. We estimated the rates for all hospitals included in the measure calculations, including those with fewer than 25 cases, using the CMS methodology and data obtained from CMS. The distribution of these rates has been previously reported.20, 21 In addition, we used the 2008 American Hospital Association (AHA) Survey to obtain data about hospital characteristics, including number of beds, hospital ownership (government, not‐for‐profit, for‐profit), teaching status (member of Council of Teaching Hospitals, other teaching hospital, nonteaching), presence of specialized cardiac capabilities (coronary artery bypass graft surgery, cardiac catheterization lab without cardiac surgery, neither), US Census Bureau core‐based statistical area (division [subarea of area with urban center >2.5 million people], metropolitan [urban center of at least 50,000 people], micropolitan [urban center of between 10,000 and 50,000 people], and rural [<10,000 people]), and safety net status22 (yes/no). Safety net status was defined as either public hospitals or private hospitals with a Medicaid caseload greater than one standard deviation above their respective state's mean private hospital Medicaid caseload using the 2007 AHA Annual Survey data.
Study Sample
This study includes 2 hospital cohorts, 1 for mortality and 1 for readmission. Hospitals were eligible for the mortality cohort if the dataset included risk‐standardized mortality rates for all 3 conditions (AMI, HF, and pneumonia). Hospitals were eligible for the readmission cohort if the dataset included risk‐standardized readmission rates for all 3 of these conditions.
Risk‐Standardized Measures
The measures include all FFS Medicare patients who are 65 years old, have been enrolled in FFS Medicare for the 12 months before the index hospitalization, are admitted with 1 of the 3 qualifying diagnoses, and do not leave the hospital against medical advice. The mortality measures include all deaths within 30 days of admission, and all deaths are attributable to the initial admitting hospital, even if the patient is then transferred to another acute care facility. Therefore, for a given hospital, transfers into the hospital are excluded from its rate, but transfers out are included. The readmission measures include all readmissions within 30 days of discharge, and all readmissions are attributable to the final discharging hospital, even if the patient was originally admitted to a different acute care facility. Therefore, for a given hospital, transfers in are included in its rate, but transfers out are excluded. For mortality measures, only 1 hospitalization for a patient in a specific year is randomly selected if the patient has multiple hospitalizations in the year. For readmission measures, admissions in which the patient died prior to discharge, and admissions within 30 days of an index admission, are not counted as index admissions.
Outcomes for all measures are all‐cause; however, for the AMI readmission measure, planned admissions for cardiac procedures are not counted as readmissions. Patients in observation status or in non‐acute care facilities are not counted as readmissions. Detailed specifications for the outcomes measures are available at the National Quality Measures Clearinghouse.23
The derivation and validation of the risk‐standardized outcome measures have been previously reported.20, 21, 2327 The measures are derived from hierarchical logistic regression models that include age, sex, clinical covariates, and a hospital‐specific random effect. The rates are calculated as the ratio of the number of predicted outcomes (obtained from a model applying the hospital‐specific effect) to the number of expected outcomes (obtained from a model applying the average effect among hospitals), multiplied by the unadjusted overall 30‐day rate.
Statistical Analysis
We examined patterns and distributions of hospital volume, risk‐standardized mortality rates, and risk‐standardized readmission rates among included hospitals. To measure the degree of association among hospitals' risk‐standardized mortality rates for AMI, HF, and pneumonia, we calculated Pearson correlation coefficients, resulting in 3 correlations for the 3 pairs of conditions (AMI and HF, AMI and pneumonia, HF and pneumonia), and tested whether they were significantly different from 0. We also conducted a factor analysis using the principal component method with a minimum eigenvalue of 1 to retain factors to determine whether there was a single common factor underlying mortality performance for the 3 conditions.28 Finally, we divided hospitals into quartiles of performance for each outcome based on the point estimate of risk‐standardized rate, and compared quartile of performance between condition pairs for each outcome. For each condition pair, we assessed the percent of hospitals in the same quartile of performance in both conditions, the percent of hospitals in either the top quartile of performance or the bottom quartile of performance for both, and the percent of hospitals in the top quartile for one and the bottom quartile for the other. We calculated the weighted kappa for agreement on quartile of performance between condition pairs for each outcome and the Spearman correlation for quartiles of performance. Then, we examined Pearson correlation coefficients in different subgroups of hospitals, including by size, ownership, teaching status, cardiac procedure capability, statistical area, and safety net status. In order to determine whether these correlations differed by hospital characteristics, we tested if the Pearson correlation coefficients were different between any 2 subgroups using the method proposed by Fisher.29 We repeated all of these analyses separately for the risk‐standardized readmission rates.
To determine whether correlations between mortality rates were significantly different than correlations between readmission rates for any given condition pair, we used the method recommended by Raghunathan et al.30 For these analyses, we included only hospitals reporting both mortality and readmission rates for the condition pairs. We used the same methods to determine whether correlations between mortality rates were significantly different than correlations between readmission rates for any given condition pair among subgroups of hospital characteristics.
All analyses and graphing were performed using the SAS statistical package version 9.2 (SAS Institute, Cary, NC). We considered a P‐value < 0.05 to be statistically significant, and all statistical tests were 2‐tailed.
RESULTS
The mortality cohort included 4559 hospitals, and the readmission cohort included 4468 hospitals. The majority of hospitals was small, nonteaching, and did not have advanced cardiac capabilities such as cardiac surgery or cardiac catheterization (Table 1).
Description | Mortality Measures | Readmission Measures |
---|---|---|
Hospital N = 4559 | Hospital N = 4468 | |
N (%)* | N (%)* | |
| ||
No. of beds | ||
>600 | 157 (3.4) | 156 (3.5) |
300600 | 628 (13.8) | 626 (14.0) |
<300 | 3588 (78.7) | 3505 (78.5) |
Unknown | 186 (4.08) | 181 (4.1) |
Mean (SD) | 173.24 (189.52) | 175.23 (190.00) |
Ownership | ||
Not‐for‐profit | 2650 (58.1) | 2619 (58.6) |
For‐profit | 672 (14.7) | 663 (14.8) |
Government | 1051 (23.1) | 1005 (22.5) |
Unknown | 186 (4.1) | 181 (4.1) |
Teaching status | ||
COTH | 277 (6.1) | 276 (6.2) |
Teaching | 505 (11.1) | 503 (11.3) |
Nonteaching | 3591 (78.8) | 3508 (78.5) |
Unknown | 186 (4.1) | 181 (4.1) |
Cardiac facility type | ||
CABG | 1471 (32.3) | 1467 (32.8) |
Cath lab | 578 (12.7) | 578 (12.9) |
Neither | 2324 (51.0) | 2242 (50.2) |
Unknown | 186 (4.1) | 181 (4.1) |
Core‐based statistical area | ||
Division | 621 (13.6) | 618 (13.8) |
Metro | 1850 (40.6) | 1835 (41.1) |
Micro | 801 (17.6) | 788 (17.6) |
Rural | 1101 (24.2) | 1046 (23.4) |
Unknown | 186 (4.1) | 181 (4.1) |
Safety net status | ||
No | 2995 (65.7) | 2967 (66.4) |
Yes | 1377 (30.2) | 1319 (29.5) |
Unknown | 187 (4.1) | 182 (4.1) |
For mortality measures, the smallest median number of cases per hospital was for AMI (48; interquartile range [IQR], 13,171), and the greatest number was for pneumonia (178; IQR, 87, 336). The same pattern held for readmission measures (AMI median 33; IQR; 9, 150; pneumonia median 191; IQR, 95, 352.5). With respect to mortality measures, AMI had the highest rate and HF the lowest rate; however, for readmission measures, HF had the highest rate and pneumonia the lowest rate (Table 2).
Description | Mortality Measures (N = 4559) | Readmission Measures (N = 4468) | ||||
---|---|---|---|---|---|---|
AMI | HF | PN | AMI | HF | PN | |
| ||||||
Total discharges | 558,653 | 1,094,960 | 1,114,706 | 546,514 | 1,314,394 | 1,152,708 |
Hospital volume | ||||||
Mean (SD) | 122.54 (172.52) | 240.18 (271.35) | 244.51 (220.74) | 122.32 (201.78) | 294.18 (333.2) | 257.99 (228.5) |
Median (IQR) | 48 (13, 171) | 142 (56, 337) | 178 (87, 336) | 33 (9, 150) | 172.5 (68, 407) | 191 (95, 352.5) |
Range min, max | 1, 1379 | 1, 2814 | 1, 2241 | 1, 1611 | 1, 3410 | 2, 2359 |
30‐Day risk‐standardized rate* | ||||||
Mean (SD) | 15.7 (1.8) | 10.9 (1.6) | 11.5 (1.9) | 19.9 (1.5) | 24.8 (2.1) | 18.5 (1.7) |
Median (IQR) | 15.7 (14.5, 16.8) | 10.8 (9.9, 11.9) | 11.3 (10.2, 12.6) | 19.9 (18.9, 20.8) | 24.7 (23.4, 26.1) | 18.4 (17.3, 19.5) |
Range min, max | 10.3, 24.6 | 6.6, 18.2 | 6.7, 20.9 | 15.2, 26.3 | 17.3, 32.4 | 13.6, 26.7 |
Every mortality measure was significantly correlated with every other mortality measure (range of correlation coefficients, 0.270.41, P < 0.0001 for all 3 correlations). For example, the correlation between risk‐standardized mortality rates (RSMR) for HF and pneumonia was 0.41. Similarly, every readmission measure was significantly correlated with every other readmission measure (range of correlation coefficients, 0.320.47; P < 0.0001 for all 3 correlations). Overall, the lowest correlation was between risk‐standardized mortality rates for AMI and pneumonia (r = 0.27), and the highest correlation was between risk‐standardized readmission rates (RSRR) for HF and pneumonia (r = 0.47) (Table 3).
Description | Mortality Measures | Readmission Measures | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
N | AMI and HF | AMI and PN | HF and PN | AMI and HF | AMI and PN | HF and PN | ||||||||
r | P | r | P | r | P | N | r | P | r | P | r | P | ||
| ||||||||||||||
All | 4559 | 0.30 | 0.27 | 0.41 | 4468 | 0.38 | 0.32 | 0.47 | ||||||
Hospitals with 25 patients | 2872 | 0.33 | 0.30 | 0.44 | 2467 | 0.44 | 0.38 | 0.51 | ||||||
No. of beds | 0.15 | 0.005 | 0.0009 | <0.0001 | <0.0001 | <0.0001 | ||||||||
>600 | 157 | 0.38 | 0.43 | 0.51 | 156 | 0.67 | 0.50 | 0.66 | ||||||
300600 | 628 | 0.29 | 0.30 | 0.49 | 626 | 0.54 | 0.45 | 0.58 | ||||||
<300 | 3588 | 0.27 | 0.23 | 0.37 | 3505 | 0.30 | 0.26 | 0.44 | ||||||
Ownership | 0.021 | 0.05 | 0.39 | 0.0004 | 0.0004 | 0.003 | ||||||||
Not‐for‐profit | 2650 | 0.32 | 0.28 | 0.42 | 2619 | 0.43 | 0.36 | 0.50 | ||||||
For‐profit | 672 | 0.30 | 0.23 | 0.40 | 663 | 0.29 | 0.22 | 0.40 | ||||||
Government | 1051 | 0.24 | 0.22 | 0.39 | 1005 | 0.32 | 0.29 | 0.45 | ||||||
Teaching status | 0.11 | 0.08 | 0.0012 | <0.0001 | 0.0002 | 0.0003 | ||||||||
COTH | 277 | 0.31 | 0.34 | 0.54 | 276 | 0.54 | 0.47 | 0.59 | ||||||
Teaching | 505 | 0.22 | 0.28 | 0.43 | 503 | 0.52 | 0.42 | 0.56 | ||||||
Nonteaching | 3591 | 0.29 | 0.24 | 0.39 | 3508 | 0.32 | 0.26 | 0.44 | ||||||
Cardiac facility type | 0.022 | 0.006 | <0.0001 | <0.0001 | 0.0006 | 0.004 | ||||||||
CABG | 1471 | 0.33 | 0.29 | 0.47 | 1467 | 0.48 | 0.37 | 0.52 | ||||||
Cath lab | 578 | 0.25 | 0.26 | 0.36 | 578 | 0.32 | 0.37 | 0.47 | ||||||
Neither | 2324 | 0.26 | 0.21 | 0.36 | 2242 | 0.28 | 0.27 | 0.44 | ||||||
Core‐based statistical area | 0.0001 | <0.0001 | 0.002 | <0.0001 | <0.0001 | <0.0001 | ||||||||
Division | 621 | 0.38 | 0.34 | 0.41 | 618 | 0.46 | 0.40 | 0.56 | ||||||
Metro | 1850 | 0.26 | 0.26 | 0.42 | 1835 | 0.38 | 0.30 | 0.40 | ||||||
Micro | 801 | 0.23 | 0.22 | 0.34 | 788 | 0.32 | 0.30 | 0.47 | ||||||
Rural | 1101 | 0.21 | 0.13 | 0.32 | 1046 | 0.22 | 0.21 | 0.44 | ||||||
Safety net status | 0.001 | 0.027 | 0.68 | 0.029 | 0.037 | 0.28 | ||||||||
No | 2995 | 0.33 | 0.28 | 0.41 | 2967 | 0.40 | 0.33 | 0.48 | ||||||
Yes | 1377 | 0.23 | 0.21 | 0.40 | 1319 | 0.34 | 0.30 | 0.45 |
Both the factor analysis for the mortality measures and the factor analysis for the readmission measures yielded only one factor with an eigenvalue >1. In each factor analysis, this single common factor kept more than half of the data based on the cumulative eigenvalue (55% for mortality measures and 60% for readmission measures). For the mortality measures, the pattern of RSMR for myocardial infarction (MI), heart failure (HF), and pneumonia (PN) in the factor was high (0.68 for MI, 0.78 for HF, and 0.76 for PN); the same was true of the RSRR in the readmission measures (0.72 for MI, 0.81 for HF, and 0.78 for PN).
For all condition pairs and both outcomes, a third or more of hospitals were in the same quartile of performance for both conditions of the pair (Table 4). Hospitals were more likely to be in the same quartile of performance if they were in the top or bottom quartile than if they were in the middle. Less than 10% of hospitals were in the top quartile for one condition in the mortality or readmission pair and in the bottom quartile for the other condition in the pair. Kappa scores for same quartile of performance between pairs of outcomes ranged from 0.16 to 0.27, and were highest for HF and pneumonia for both mortality and readmission rates.
Condition Pair | Same Quartile (Any) (%) | Same Quartile (Q1 or Q4) (%) | Q1 in One and Q4 in Another (%) | Weighted Kappa | Spearman Correlation |
---|---|---|---|---|---|
| |||||
Mortality | |||||
MI and HF | 34.8 | 20.2 | 7.9 | 0.19 | 0.25 |
MI and PN | 32.7 | 18.8 | 8.2 | 0.16 | 0.22 |
HF and PN | 35.9 | 21.8 | 5.0 | 0.26 | 0.36 |
Readmission | |||||
MI and HF | 36.6 | 21.0 | 7.5 | 0.22 | 0.28 |
MI and PN | 34.0 | 19.6 | 8.1 | 0.19 | 0.24 |
HF and PN | 37.1 | 22.6 | 5.4 | 0.27 | 0.37 |
In subgroup analyses, the highest mortality correlation was between HF and pneumonia in hospitals with more than 600 beds (r = 0.51, P = 0.0009), and the highest readmission correlation was between AMI and HF in hospitals with more than 600 beds (r = 0.67, P < 0.0001). Across both measures and all 3 condition pairs, correlations between conditions increased with increasing hospital bed size, presence of cardiac surgery capability, and increasing population of the hospital's Census Bureau statistical area. Furthermore, for most measures and condition pairs, correlations between conditions were highest in not‐for‐profit hospitals, hospitals belonging to the Council of Teaching Hospitals, and non‐safety net hospitals (Table 3).
For all condition pairs, the correlation between readmission rates was significantly higher than the correlation between mortality rates (P < 0.01). In subgroup analyses, readmission correlations were also significantly higher than mortality correlations for all pairs of conditions among moderate‐sized hospitals, among nonprofit hospitals, among teaching hospitals that did not belong to the Council of Teaching Hospitals, and among non‐safety net hospitals (Table 5).
Description | AMI and HF | AMI and PN | HF and PN | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
N | MC | RC | P | N | MC | RC | P | N | MC | RC | P | |
| ||||||||||||
All | 4457 | 0.31 | 0.38 | <0.0001 | 4459 | 0.27 | 0.32 | 0.007 | 4731 | 0.41 | 0.46 | 0.0004 |
Hospitals with 25 patients | 2472 | 0.33 | 0.44 | <0.001 | 2463 | 0.31 | 0.38 | 0.01 | 4104 | 0.42 | 0.47 | 0.001 |
No. of beds | ||||||||||||
>600 | 156 | 0.38 | 0.67 | 0.0002 | 156 | 0.43 | 0.50 | 0.48 | 160 | 0.51 | 0.66 | 0.042 |
300600 | 626 | 0.29 | 0.54 | <0.0001 | 626 | 0.31 | 0.45 | 0.003 | 630 | 0.49 | 0.58 | 0.033 |
<300 | 3494 | 0.28 | 0.30 | 0.21 | 3496 | 0.23 | 0.26 | 0.17 | 3733 | 0.37 | 0.43 | 0.003 |
Ownership | ||||||||||||
Not‐for‐profit | 2614 | 0.32 | 0.43 | <0.0001 | 2617 | 0.28 | 0.36 | 0.003 | 2697 | 0.42 | 0.50 | 0.0003 |
For‐profit | 662 | 0.30 | 0.29 | 0.90 | 661 | 0.23 | 0.22 | 0.75 | 699 | 0.40 | 0.40 | 0.99 |
Government | 1000 | 0.25 | 0.32 | 0.09 | 1000 | 0.22 | 0.29 | 0.09 | 1127 | 0.39 | 0.43 | 0.21 |
Teaching status | ||||||||||||
COTH | 276 | 0.31 | 0.54 | 0.001 | 277 | 0.35 | 0.46 | 0.10 | 278 | 0.54 | 0.59 | 0.41 |
Teaching | 504 | 0.22 | 0.52 | <0.0001 | 504 | 0.28 | 0.42 | 0.012 | 508 | 0.43 | 0.56 | 0.005 |
Nonteaching | 3496 | 0.29 | 0.32 | 0.18 | 3497 | 0.24 | 0.26 | 0.46 | 3737 | 0.39 | 0.43 | 0.016 |
Cardiac facility type | ||||||||||||
CABG | 1465 | 0.33 | 0.48 | <0.0001 | 1467 | 0.30 | 0.37 | 0.018 | 1483 | 0.47 | 0.51 | 0.103 |
Cath lab | 577 | 0.25 | 0.32 | 0.18 | 577 | 0.26 | 0.37 | 0.046 | 579 | 0.36 | 0.47 | 0.022 |
Neither | 2234 | 0.26 | 0.28 | 0.48 | 2234 | 0.21 | 0.27 | 0.037 | 2461 | 0.36 | 0.44 | 0.002 |
Core‐based statistical area | ||||||||||||
Division | 618 | 0.38 | 0.46 | 0.09 | 620 | 0.34 | 0.40 | 0.18 | 630 | 0.41 | 0.56 | 0.001 |
Metro | 1833 | 0.26 | 0.38 | <0.0001 | 1832 | 0.26 | 0.30 | 0.21 | 1896 | 0.42 | 0.40 | 0.63 |
Micro | 787 | 0.24 | 0.32 | 0.08 | 787 | 0.22 | 0.30 | 0.11 | 820 | 0.34 | 0.46 | 0.003 |
Rural | 1038 | 0.21 | 0.22 | 0.83 | 1039 | 0.13 | 0.21 | 0.056 | 1177 | 0.32 | 0.43 | 0.002 |
Safety net status | ||||||||||||
No | 2961 | 0.33 | 0.40 | 0.001 | 2963 | 0.28 | 0.33 | 0.036 | 3062 | 0.41 | 0.48 | 0.001 |
Yes | 1314 | 0.23 | 0.34 | 0.003 | 1314 | 0.22 | 0.30 | 0.015 | 1460 | 0.40 | 0.45 | 0.14 |
DISCUSSION
In this study, we found that risk‐standardized mortality rates for 3 common medical conditions were moderately correlated within institutions, as were risk‐standardized readmission rates. Readmission rates were more strongly correlated than mortality rates, and all rates tracked closest together in large, urban, and/or teaching hospitals. Very few hospitals were in the top quartile of performance for one condition and in the bottom quartile for a different condition.
Our findings are consistent with the hypothesis that 30‐day risk‐standardized mortality and 30‐day risk‐standardized readmission rates, in part, capture broad aspects of hospital quality that transcend condition‐specific activities. In this study, readmission rates tracked better together than mortality rates for every pair of conditions, suggesting that there may be a greater contribution of hospital‐wide environment, structure, and processes to readmission rates than to mortality rates. This difference is plausible because services specific to readmission, such as discharge planning, care coordination, medication reconciliation, and discharge communication with patients and outpatient clinicians, are typically hospital‐wide processes.
Our study differs from earlier studies of medical conditions in that the correlations we found were higher.18, 19 There are several possible explanations for this difference. First, during the intervening 1525 years since those studies were performed, care for these conditions has evolved substantially, such that there are now more standardized protocols available for all 3 of these diseases. Hospitals that are sufficiently organized or acculturated to systematically implement care protocols may have the infrastructure or culture to do so for all conditions, increasing correlation of performance among conditions. In addition, there are now more technologies and systems available that span care for multiple conditions, such as electronic medical records and quality committees, than were available in previous generations. Second, one of these studies utilized less robust risk‐adjustment,18 and neither used the same methodology of risk standardization. Nonetheless, it is interesting to note that Rosenthal and colleagues identified the same increase in correlation with higher volumes than we did.19 Studies investigating mortality correlations among surgical procedures, on the other hand, have generally found higher correlations than we found in these medical conditions.16, 17
Accountable care organizations will be assessed using an all‐condition readmission measure,31 several states track all‐condition readmission rates,3234 and several countries measure all‐condition mortality.35 An all‐condition measure for quality assessment first requires that there be a hospital‐wide quality signal above and beyond disease‐specific care. This study suggests that a moderate signal exists for readmission and, to a slightly lesser extent, for mortality, across 3 common conditions. There are other considerations, however, in developing all‐condition measures. There must be adequate risk adjustment for the wide variety of conditions that are included, and there must be a means of accounting for the variation in types of conditions and procedures cared for by different hospitals. Our study does not address these challenges, which have been described to be substantial for mortality measures.35
We were surprised by the finding that risk‐standardized rates correlated more strongly within larger institutions than smaller ones, because one might assume that care within smaller hospitals might be more homogenous. It may be easier, however, to detect a quality signal in hospitals with higher volumes of patients for all 3 conditions, because estimates for these hospitals are more precise. Consequently, we have greater confidence in results for larger volumes, and suspect a similar quality signal may be present but more difficult to detect statistically in smaller hospitals. Overall correlations were higher when we restricted the sample to hospitals with at least 25 cases, as is used for public reporting. It is also possible that the finding is real given that large‐volume hospitals have been demonstrated to provide better care for these conditions and are more likely to adopt systems of care that affect multiple conditions, such as electronic medical records.14, 36
The kappa scores comparing quartile of national performance for pairs of conditions were only in the fair range. There are several possible explanations for this fact: 1) outcomes for these 3 conditions are not measuring the same constructs; 2) they are all measuring the same construct, but they are unreliable in doing so; and/or 3) hospitals have similar latent quality for all 3 conditions, but the national quality of performance differs by condition, yielding variable relative performance per hospital for each condition. Based solely on our findings, we cannot distinguish which, if any, of these explanations may be true.31
Our study has several limitations. First, all 3 conditions currently publicly reported by CMS are medical diagnoses, although AMI patients may be cared for in distinct cardiology units and often undergo procedures; therefore, we cannot determine the degree to which correlations reflect hospital‐wide quality versus medicine‐wide quality. An institution may have a weak medicine department but a strong surgical department or vice versa. Second, it is possible that the correlations among conditions for readmission and among conditions for mortality are attributable to patient characteristics that are not adequately adjusted for in the risk‐adjustment model, such as socioeconomic factors, or to hospital characteristics not related to quality, such as coding practices or inter‐hospital transfer rates. For this to be true, these unmeasured characteristics would have to be consistent across different conditions within each hospital and have a consistent influence on outcomes. Third, it is possible that public reporting may have prompted disease‐specific focus on these conditions. We do not have data from non‐publicly reported conditions to test this hypothesis. Fourth, there are many small‐volume hospitals in this study; their estimates for readmission and mortality are less reliable than for large‐volume hospitals, potentially limiting our ability to detect correlations in this group of hospitals.
This study lends credence to the hypothesis that 30‐day risk‐standardized mortality and readmission rates for individual conditions may reflect aspects of hospital‐wide quality or at least medicine‐wide quality, although the correlations are not large enough to conclude that hospital‐wide factors play a dominant role, and there are other possible explanations for the correlations. Further work is warranted to better understand the causes of the correlations, and to better specify the nature of hospital factors that contribute to correlations among outcomes.
Acknowledgements
Disclosures: Dr Horwitz is supported by the National Institute on Aging (K08 AG038336) and by the American Federation of Aging Research through the Paul B. Beeson Career Development Award Program. Dr Horwitz is also a Pepper Scholar with support from the Claude D. Pepper Older Americans Independence Center at Yale University School of Medicine (P30 AG021342 NIH/NIA). Dr Krumholz is supported by grant U01 HL105270‐01 (Center for Cardiovascular Outcomes Research at Yale University) from the National Heart, Lung, and Blood Institute. Dr Krumholz chairs a cardiac scientific advisory board for UnitedHealth. Authors Drye, Krumholz, and Wang receive support from the Centers for Medicare & Medicaid Services (CMS) to develop and maintain performance measures that are used for public reporting. The analyses upon which this publication is based were performed under Contract Number HHSM‐500‐2008‐0025I Task Order T0001, entitled Measure & Instrument Development and Support (MIDS)Development and Re‐evaluation of the CMS Hospital Outcomes and Efficiency Measures, funded by the Centers for Medicare & Medicaid Services, an agency of the US Department of Health and Human Services. The Centers for Medicare & Medicaid Services reviewed and approved the use of its data for this work, and approved submission of the manuscript. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government. The authors assume full responsibility for the accuracy and completeness of the ideas presented.
The Centers for Medicare & Medicaid Services (CMS) publicly reports hospital‐specific, 30‐day risk‐standardized mortality and readmission rates for Medicare fee‐for‐service patients admitted with acute myocardial infarction (AMI), heart failure (HF), and pneumonia.1 These measures are intended to reflect hospital performance on quality of care provided to patients during and after hospitalization.2, 3
Quality‐of‐care measures for a given disease are often assumed to reflect the quality of care for that particular condition. However, studies have found limited association between condition‐specific process measures and either mortality or readmission rates for those conditions.46 Mortality and readmission rates may instead reflect broader hospital‐wide or specialty‐wide structure, culture, and practice. For example, studies have previously found that hospitals differ in mortality or readmission rates according to organizational structure,7 financial structure,8 culture,9, 10 information technology,11 patient volume,1214 academic status,12 and other institution‐wide factors.12 There is now a strong policy push towards developing hospital‐wide (all‐condition) measures, beginning with readmission.15
It is not clear how much of the quality of care for a given condition is attributable to hospital‐wide influences that affect all conditions rather than disease‐specific factors. If readmission or mortality performance for a particular condition reflects, in large part, broader institutional characteristics, then improvement efforts might better be focused on hospital‐wide activities, such as team training or implementing electronic medical records. On the other hand, if the disease‐specific measures reflect quality strictly for those conditions, then improvement efforts would be better focused on disease‐specific care, such as early identification of the relevant patient population or standardizing disease‐specific care. As hospitals work to improve performance across an increasingly wide variety of conditions, it is becoming more important for hospitals to prioritize and focus their activities effectively and efficiently.
One means of determining the relative contribution of hospital versus disease factors is to explore whether outcome rates are consistent among different conditions cared for in the same hospital. If mortality (or readmission) rates across different conditions are highly correlated, it would suggest that hospital‐wide factors may play a substantive role in outcomes. Some studies have found that mortality for a particular surgical condition is a useful proxy for mortality for other surgical conditions,16, 17 while other studies have found little correlation among mortality rates for various medical conditions.18, 19 It is also possible that correlation varies according to hospital characteristics; for example, smaller or nonteaching hospitals might be more homogenous in their care than larger, less homogeneous institutions. No studies have been performed using publicly reported estimates of risk‐standardized mortality or readmission rates. In this study we use the publicly reported measures of 30‐day mortality and 30‐day readmission for AMI, HF, and pneumonia to examine whether, and to what degree, mortality rates track together within US hospitals, and separately, to what degree readmission rates track together within US hospitals.
METHODS
Data Sources
CMS calculates risk‐standardized mortality and readmission rates, and patient volume, for all acute care nonfederal hospitals with one or more eligible case of AMI, HF, and pneumonia annually based on fee‐for‐service (FFS) Medicare claims. CMS publicly releases the rates for the large subset of hospitals that participate in public reporting and have 25 or more cases for the conditions over the 3‐year period between July 2006 and June 2009. We estimated the rates for all hospitals included in the measure calculations, including those with fewer than 25 cases, using the CMS methodology and data obtained from CMS. The distribution of these rates has been previously reported.20, 21 In addition, we used the 2008 American Hospital Association (AHA) Survey to obtain data about hospital characteristics, including number of beds, hospital ownership (government, not‐for‐profit, for‐profit), teaching status (member of Council of Teaching Hospitals, other teaching hospital, nonteaching), presence of specialized cardiac capabilities (coronary artery bypass graft surgery, cardiac catheterization lab without cardiac surgery, neither), US Census Bureau core‐based statistical area (division [subarea of area with urban center >2.5 million people], metropolitan [urban center of at least 50,000 people], micropolitan [urban center of between 10,000 and 50,000 people], and rural [<10,000 people]), and safety net status22 (yes/no). Safety net status was defined as either public hospitals or private hospitals with a Medicaid caseload greater than one standard deviation above their respective state's mean private hospital Medicaid caseload using the 2007 AHA Annual Survey data.
Study Sample
This study includes 2 hospital cohorts, 1 for mortality and 1 for readmission. Hospitals were eligible for the mortality cohort if the dataset included risk‐standardized mortality rates for all 3 conditions (AMI, HF, and pneumonia). Hospitals were eligible for the readmission cohort if the dataset included risk‐standardized readmission rates for all 3 of these conditions.
Risk‐Standardized Measures
The measures include all FFS Medicare patients who are 65 years old, have been enrolled in FFS Medicare for the 12 months before the index hospitalization, are admitted with 1 of the 3 qualifying diagnoses, and do not leave the hospital against medical advice. The mortality measures include all deaths within 30 days of admission, and all deaths are attributable to the initial admitting hospital, even if the patient is then transferred to another acute care facility. Therefore, for a given hospital, transfers into the hospital are excluded from its rate, but transfers out are included. The readmission measures include all readmissions within 30 days of discharge, and all readmissions are attributable to the final discharging hospital, even if the patient was originally admitted to a different acute care facility. Therefore, for a given hospital, transfers in are included in its rate, but transfers out are excluded. For mortality measures, only 1 hospitalization for a patient in a specific year is randomly selected if the patient has multiple hospitalizations in the year. For readmission measures, admissions in which the patient died prior to discharge, and admissions within 30 days of an index admission, are not counted as index admissions.
Outcomes for all measures are all‐cause; however, for the AMI readmission measure, planned admissions for cardiac procedures are not counted as readmissions. Patients in observation status or in non‐acute care facilities are not counted as readmissions. Detailed specifications for the outcomes measures are available at the National Quality Measures Clearinghouse.23
The derivation and validation of the risk‐standardized outcome measures have been previously reported.20, 21, 2327 The measures are derived from hierarchical logistic regression models that include age, sex, clinical covariates, and a hospital‐specific random effect. The rates are calculated as the ratio of the number of predicted outcomes (obtained from a model applying the hospital‐specific effect) to the number of expected outcomes (obtained from a model applying the average effect among hospitals), multiplied by the unadjusted overall 30‐day rate.
Statistical Analysis
We examined patterns and distributions of hospital volume, risk‐standardized mortality rates, and risk‐standardized readmission rates among included hospitals. To measure the degree of association among hospitals' risk‐standardized mortality rates for AMI, HF, and pneumonia, we calculated Pearson correlation coefficients, resulting in 3 correlations for the 3 pairs of conditions (AMI and HF, AMI and pneumonia, HF and pneumonia), and tested whether they were significantly different from 0. We also conducted a factor analysis using the principal component method with a minimum eigenvalue of 1 to retain factors to determine whether there was a single common factor underlying mortality performance for the 3 conditions.28 Finally, we divided hospitals into quartiles of performance for each outcome based on the point estimate of risk‐standardized rate, and compared quartile of performance between condition pairs for each outcome. For each condition pair, we assessed the percent of hospitals in the same quartile of performance in both conditions, the percent of hospitals in either the top quartile of performance or the bottom quartile of performance for both, and the percent of hospitals in the top quartile for one and the bottom quartile for the other. We calculated the weighted kappa for agreement on quartile of performance between condition pairs for each outcome and the Spearman correlation for quartiles of performance. Then, we examined Pearson correlation coefficients in different subgroups of hospitals, including by size, ownership, teaching status, cardiac procedure capability, statistical area, and safety net status. In order to determine whether these correlations differed by hospital characteristics, we tested if the Pearson correlation coefficients were different between any 2 subgroups using the method proposed by Fisher.29 We repeated all of these analyses separately for the risk‐standardized readmission rates.
To determine whether correlations between mortality rates were significantly different than correlations between readmission rates for any given condition pair, we used the method recommended by Raghunathan et al.30 For these analyses, we included only hospitals reporting both mortality and readmission rates for the condition pairs. We used the same methods to determine whether correlations between mortality rates were significantly different than correlations between readmission rates for any given condition pair among subgroups of hospital characteristics.
All analyses and graphing were performed using the SAS statistical package version 9.2 (SAS Institute, Cary, NC). We considered a P‐value < 0.05 to be statistically significant, and all statistical tests were 2‐tailed.
RESULTS
The mortality cohort included 4559 hospitals, and the readmission cohort included 4468 hospitals. The majority of hospitals was small, nonteaching, and did not have advanced cardiac capabilities such as cardiac surgery or cardiac catheterization (Table 1).
Description | Mortality Measures | Readmission Measures |
---|---|---|
Hospital N = 4559 | Hospital N = 4468 | |
N (%)* | N (%)* | |
| ||
No. of beds | ||
>600 | 157 (3.4) | 156 (3.5) |
300600 | 628 (13.8) | 626 (14.0) |
<300 | 3588 (78.7) | 3505 (78.5) |
Unknown | 186 (4.08) | 181 (4.1) |
Mean (SD) | 173.24 (189.52) | 175.23 (190.00) |
Ownership | ||
Not‐for‐profit | 2650 (58.1) | 2619 (58.6) |
For‐profit | 672 (14.7) | 663 (14.8) |
Government | 1051 (23.1) | 1005 (22.5) |
Unknown | 186 (4.1) | 181 (4.1) |
Teaching status | ||
COTH | 277 (6.1) | 276 (6.2) |
Teaching | 505 (11.1) | 503 (11.3) |
Nonteaching | 3591 (78.8) | 3508 (78.5) |
Unknown | 186 (4.1) | 181 (4.1) |
Cardiac facility type | ||
CABG | 1471 (32.3) | 1467 (32.8) |
Cath lab | 578 (12.7) | 578 (12.9) |
Neither | 2324 (51.0) | 2242 (50.2) |
Unknown | 186 (4.1) | 181 (4.1) |
Core‐based statistical area | ||
Division | 621 (13.6) | 618 (13.8) |
Metro | 1850 (40.6) | 1835 (41.1) |
Micro | 801 (17.6) | 788 (17.6) |
Rural | 1101 (24.2) | 1046 (23.4) |
Unknown | 186 (4.1) | 181 (4.1) |
Safety net status | ||
No | 2995 (65.7) | 2967 (66.4) |
Yes | 1377 (30.2) | 1319 (29.5) |
Unknown | 187 (4.1) | 182 (4.1) |
For mortality measures, the smallest median number of cases per hospital was for AMI (48; interquartile range [IQR], 13,171), and the greatest number was for pneumonia (178; IQR, 87, 336). The same pattern held for readmission measures (AMI median 33; IQR; 9, 150; pneumonia median 191; IQR, 95, 352.5). With respect to mortality measures, AMI had the highest rate and HF the lowest rate; however, for readmission measures, HF had the highest rate and pneumonia the lowest rate (Table 2).
Description | Mortality Measures (N = 4559) | Readmission Measures (N = 4468) | ||||
---|---|---|---|---|---|---|
AMI | HF | PN | AMI | HF | PN | |
| ||||||
Total discharges | 558,653 | 1,094,960 | 1,114,706 | 546,514 | 1,314,394 | 1,152,708 |
Hospital volume | ||||||
Mean (SD) | 122.54 (172.52) | 240.18 (271.35) | 244.51 (220.74) | 122.32 (201.78) | 294.18 (333.2) | 257.99 (228.5) |
Median (IQR) | 48 (13, 171) | 142 (56, 337) | 178 (87, 336) | 33 (9, 150) | 172.5 (68, 407) | 191 (95, 352.5) |
Range min, max | 1, 1379 | 1, 2814 | 1, 2241 | 1, 1611 | 1, 3410 | 2, 2359 |
30‐Day risk‐standardized rate* | ||||||
Mean (SD) | 15.7 (1.8) | 10.9 (1.6) | 11.5 (1.9) | 19.9 (1.5) | 24.8 (2.1) | 18.5 (1.7) |
Median (IQR) | 15.7 (14.5, 16.8) | 10.8 (9.9, 11.9) | 11.3 (10.2, 12.6) | 19.9 (18.9, 20.8) | 24.7 (23.4, 26.1) | 18.4 (17.3, 19.5) |
Range min, max | 10.3, 24.6 | 6.6, 18.2 | 6.7, 20.9 | 15.2, 26.3 | 17.3, 32.4 | 13.6, 26.7 |
Every mortality measure was significantly correlated with every other mortality measure (range of correlation coefficients, 0.270.41, P < 0.0001 for all 3 correlations). For example, the correlation between risk‐standardized mortality rates (RSMR) for HF and pneumonia was 0.41. Similarly, every readmission measure was significantly correlated with every other readmission measure (range of correlation coefficients, 0.320.47; P < 0.0001 for all 3 correlations). Overall, the lowest correlation was between risk‐standardized mortality rates for AMI and pneumonia (r = 0.27), and the highest correlation was between risk‐standardized readmission rates (RSRR) for HF and pneumonia (r = 0.47) (Table 3).
Description | Mortality Measures | Readmission Measures | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
N | AMI and HF | AMI and PN | HF and PN | AMI and HF | AMI and PN | HF and PN | ||||||||
r | P | r | P | r | P | N | r | P | r | P | r | P | ||
| ||||||||||||||
All | 4559 | 0.30 | 0.27 | 0.41 | 4468 | 0.38 | 0.32 | 0.47 | ||||||
Hospitals with 25 patients | 2872 | 0.33 | 0.30 | 0.44 | 2467 | 0.44 | 0.38 | 0.51 | ||||||
No. of beds | 0.15 | 0.005 | 0.0009 | <0.0001 | <0.0001 | <0.0001 | ||||||||
>600 | 157 | 0.38 | 0.43 | 0.51 | 156 | 0.67 | 0.50 | 0.66 | ||||||
300600 | 628 | 0.29 | 0.30 | 0.49 | 626 | 0.54 | 0.45 | 0.58 | ||||||
<300 | 3588 | 0.27 | 0.23 | 0.37 | 3505 | 0.30 | 0.26 | 0.44 | ||||||
Ownership | 0.021 | 0.05 | 0.39 | 0.0004 | 0.0004 | 0.003 | ||||||||
Not‐for‐profit | 2650 | 0.32 | 0.28 | 0.42 | 2619 | 0.43 | 0.36 | 0.50 | ||||||
For‐profit | 672 | 0.30 | 0.23 | 0.40 | 663 | 0.29 | 0.22 | 0.40 | ||||||
Government | 1051 | 0.24 | 0.22 | 0.39 | 1005 | 0.32 | 0.29 | 0.45 | ||||||
Teaching status | 0.11 | 0.08 | 0.0012 | <0.0001 | 0.0002 | 0.0003 | ||||||||
COTH | 277 | 0.31 | 0.34 | 0.54 | 276 | 0.54 | 0.47 | 0.59 | ||||||
Teaching | 505 | 0.22 | 0.28 | 0.43 | 503 | 0.52 | 0.42 | 0.56 | ||||||
Nonteaching | 3591 | 0.29 | 0.24 | 0.39 | 3508 | 0.32 | 0.26 | 0.44 | ||||||
Cardiac facility type | 0.022 | 0.006 | <0.0001 | <0.0001 | 0.0006 | 0.004 | ||||||||
CABG | 1471 | 0.33 | 0.29 | 0.47 | 1467 | 0.48 | 0.37 | 0.52 | ||||||
Cath lab | 578 | 0.25 | 0.26 | 0.36 | 578 | 0.32 | 0.37 | 0.47 | ||||||
Neither | 2324 | 0.26 | 0.21 | 0.36 | 2242 | 0.28 | 0.27 | 0.44 | ||||||
Core‐based statistical area | 0.0001 | <0.0001 | 0.002 | <0.0001 | <0.0001 | <0.0001 | ||||||||
Division | 621 | 0.38 | 0.34 | 0.41 | 618 | 0.46 | 0.40 | 0.56 | ||||||
Metro | 1850 | 0.26 | 0.26 | 0.42 | 1835 | 0.38 | 0.30 | 0.40 | ||||||
Micro | 801 | 0.23 | 0.22 | 0.34 | 788 | 0.32 | 0.30 | 0.47 | ||||||
Rural | 1101 | 0.21 | 0.13 | 0.32 | 1046 | 0.22 | 0.21 | 0.44 | ||||||
Safety net status | 0.001 | 0.027 | 0.68 | 0.029 | 0.037 | 0.28 | ||||||||
No | 2995 | 0.33 | 0.28 | 0.41 | 2967 | 0.40 | 0.33 | 0.48 | ||||||
Yes | 1377 | 0.23 | 0.21 | 0.40 | 1319 | 0.34 | 0.30 | 0.45 |
Both the factor analysis for the mortality measures and the factor analysis for the readmission measures yielded only one factor with an eigenvalue >1. In each factor analysis, this single common factor kept more than half of the data based on the cumulative eigenvalue (55% for mortality measures and 60% for readmission measures). For the mortality measures, the pattern of RSMR for myocardial infarction (MI), heart failure (HF), and pneumonia (PN) in the factor was high (0.68 for MI, 0.78 for HF, and 0.76 for PN); the same was true of the RSRR in the readmission measures (0.72 for MI, 0.81 for HF, and 0.78 for PN).
For all condition pairs and both outcomes, a third or more of hospitals were in the same quartile of performance for both conditions of the pair (Table 4). Hospitals were more likely to be in the same quartile of performance if they were in the top or bottom quartile than if they were in the middle. Less than 10% of hospitals were in the top quartile for one condition in the mortality or readmission pair and in the bottom quartile for the other condition in the pair. Kappa scores for same quartile of performance between pairs of outcomes ranged from 0.16 to 0.27, and were highest for HF and pneumonia for both mortality and readmission rates.
Condition Pair | Same Quartile (Any) (%) | Same Quartile (Q1 or Q4) (%) | Q1 in One and Q4 in Another (%) | Weighted Kappa | Spearman Correlation |
---|---|---|---|---|---|
| |||||
Mortality | |||||
MI and HF | 34.8 | 20.2 | 7.9 | 0.19 | 0.25 |
MI and PN | 32.7 | 18.8 | 8.2 | 0.16 | 0.22 |
HF and PN | 35.9 | 21.8 | 5.0 | 0.26 | 0.36 |
Readmission | |||||
MI and HF | 36.6 | 21.0 | 7.5 | 0.22 | 0.28 |
MI and PN | 34.0 | 19.6 | 8.1 | 0.19 | 0.24 |
HF and PN | 37.1 | 22.6 | 5.4 | 0.27 | 0.37 |
In subgroup analyses, the highest mortality correlation was between HF and pneumonia in hospitals with more than 600 beds (r = 0.51, P = 0.0009), and the highest readmission correlation was between AMI and HF in hospitals with more than 600 beds (r = 0.67, P < 0.0001). Across both measures and all 3 condition pairs, correlations between conditions increased with increasing hospital bed size, presence of cardiac surgery capability, and increasing population of the hospital's Census Bureau statistical area. Furthermore, for most measures and condition pairs, correlations between conditions were highest in not‐for‐profit hospitals, hospitals belonging to the Council of Teaching Hospitals, and non‐safety net hospitals (Table 3).
For all condition pairs, the correlation between readmission rates was significantly higher than the correlation between mortality rates (P < 0.01). In subgroup analyses, readmission correlations were also significantly higher than mortality correlations for all pairs of conditions among moderate‐sized hospitals, among nonprofit hospitals, among teaching hospitals that did not belong to the Council of Teaching Hospitals, and among non‐safety net hospitals (Table 5).
Description | AMI and HF | AMI and PN | HF and PN | |||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
N | MC | RC | P | N | MC | RC | P | N | MC | RC | P | |
| ||||||||||||
All | 4457 | 0.31 | 0.38 | <0.0001 | 4459 | 0.27 | 0.32 | 0.007 | 4731 | 0.41 | 0.46 | 0.0004 |
Hospitals with 25 patients | 2472 | 0.33 | 0.44 | <0.001 | 2463 | 0.31 | 0.38 | 0.01 | 4104 | 0.42 | 0.47 | 0.001 |
No. of beds | ||||||||||||
>600 | 156 | 0.38 | 0.67 | 0.0002 | 156 | 0.43 | 0.50 | 0.48 | 160 | 0.51 | 0.66 | 0.042 |
300600 | 626 | 0.29 | 0.54 | <0.0001 | 626 | 0.31 | 0.45 | 0.003 | 630 | 0.49 | 0.58 | 0.033 |
<300 | 3494 | 0.28 | 0.30 | 0.21 | 3496 | 0.23 | 0.26 | 0.17 | 3733 | 0.37 | 0.43 | 0.003 |
Ownership | ||||||||||||
Not‐for‐profit | 2614 | 0.32 | 0.43 | <0.0001 | 2617 | 0.28 | 0.36 | 0.003 | 2697 | 0.42 | 0.50 | 0.0003 |
For‐profit | 662 | 0.30 | 0.29 | 0.90 | 661 | 0.23 | 0.22 | 0.75 | 699 | 0.40 | 0.40 | 0.99 |
Government | 1000 | 0.25 | 0.32 | 0.09 | 1000 | 0.22 | 0.29 | 0.09 | 1127 | 0.39 | 0.43 | 0.21 |
Teaching status | ||||||||||||
COTH | 276 | 0.31 | 0.54 | 0.001 | 277 | 0.35 | 0.46 | 0.10 | 278 | 0.54 | 0.59 | 0.41 |
Teaching | 504 | 0.22 | 0.52 | <0.0001 | 504 | 0.28 | 0.42 | 0.012 | 508 | 0.43 | 0.56 | 0.005 |
Nonteaching | 3496 | 0.29 | 0.32 | 0.18 | 3497 | 0.24 | 0.26 | 0.46 | 3737 | 0.39 | 0.43 | 0.016 |
Cardiac facility type | ||||||||||||
CABG | 1465 | 0.33 | 0.48 | <0.0001 | 1467 | 0.30 | 0.37 | 0.018 | 1483 | 0.47 | 0.51 | 0.103 |
Cath lab | 577 | 0.25 | 0.32 | 0.18 | 577 | 0.26 | 0.37 | 0.046 | 579 | 0.36 | 0.47 | 0.022 |
Neither | 2234 | 0.26 | 0.28 | 0.48 | 2234 | 0.21 | 0.27 | 0.037 | 2461 | 0.36 | 0.44 | 0.002 |
Core‐based statistical area | ||||||||||||
Division | 618 | 0.38 | 0.46 | 0.09 | 620 | 0.34 | 0.40 | 0.18 | 630 | 0.41 | 0.56 | 0.001 |
Metro | 1833 | 0.26 | 0.38 | <0.0001 | 1832 | 0.26 | 0.30 | 0.21 | 1896 | 0.42 | 0.40 | 0.63 |
Micro | 787 | 0.24 | 0.32 | 0.08 | 787 | 0.22 | 0.30 | 0.11 | 820 | 0.34 | 0.46 | 0.003 |
Rural | 1038 | 0.21 | 0.22 | 0.83 | 1039 | 0.13 | 0.21 | 0.056 | 1177 | 0.32 | 0.43 | 0.002 |
Safety net status | ||||||||||||
No | 2961 | 0.33 | 0.40 | 0.001 | 2963 | 0.28 | 0.33 | 0.036 | 3062 | 0.41 | 0.48 | 0.001 |
Yes | 1314 | 0.23 | 0.34 | 0.003 | 1314 | 0.22 | 0.30 | 0.015 | 1460 | 0.40 | 0.45 | 0.14 |
DISCUSSION
In this study, we found that risk‐standardized mortality rates for 3 common medical conditions were moderately correlated within institutions, as were risk‐standardized readmission rates. Readmission rates were more strongly correlated than mortality rates, and all rates tracked closest together in large, urban, and/or teaching hospitals. Very few hospitals were in the top quartile of performance for one condition and in the bottom quartile for a different condition.
Our findings are consistent with the hypothesis that 30‐day risk‐standardized mortality and 30‐day risk‐standardized readmission rates, in part, capture broad aspects of hospital quality that transcend condition‐specific activities. In this study, readmission rates tracked better together than mortality rates for every pair of conditions, suggesting that there may be a greater contribution of hospital‐wide environment, structure, and processes to readmission rates than to mortality rates. This difference is plausible because services specific to readmission, such as discharge planning, care coordination, medication reconciliation, and discharge communication with patients and outpatient clinicians, are typically hospital‐wide processes.
Our study differs from earlier studies of medical conditions in that the correlations we found were higher.18, 19 There are several possible explanations for this difference. First, during the intervening 1525 years since those studies were performed, care for these conditions has evolved substantially, such that there are now more standardized protocols available for all 3 of these diseases. Hospitals that are sufficiently organized or acculturated to systematically implement care protocols may have the infrastructure or culture to do so for all conditions, increasing correlation of performance among conditions. In addition, there are now more technologies and systems available that span care for multiple conditions, such as electronic medical records and quality committees, than were available in previous generations. Second, one of these studies utilized less robust risk‐adjustment,18 and neither used the same methodology of risk standardization. Nonetheless, it is interesting to note that Rosenthal and colleagues identified the same increase in correlation with higher volumes than we did.19 Studies investigating mortality correlations among surgical procedures, on the other hand, have generally found higher correlations than we found in these medical conditions.16, 17
Accountable care organizations will be assessed using an all‐condition readmission measure,31 several states track all‐condition readmission rates,3234 and several countries measure all‐condition mortality.35 An all‐condition measure for quality assessment first requires that there be a hospital‐wide quality signal above and beyond disease‐specific care. This study suggests that a moderate signal exists for readmission and, to a slightly lesser extent, for mortality, across 3 common conditions. There are other considerations, however, in developing all‐condition measures. There must be adequate risk adjustment for the wide variety of conditions that are included, and there must be a means of accounting for the variation in types of conditions and procedures cared for by different hospitals. Our study does not address these challenges, which have been described to be substantial for mortality measures.35
We were surprised by the finding that risk‐standardized rates correlated more strongly within larger institutions than smaller ones, because one might assume that care within smaller hospitals might be more homogenous. It may be easier, however, to detect a quality signal in hospitals with higher volumes of patients for all 3 conditions, because estimates for these hospitals are more precise. Consequently, we have greater confidence in results for larger volumes, and suspect a similar quality signal may be present but more difficult to detect statistically in smaller hospitals. Overall correlations were higher when we restricted the sample to hospitals with at least 25 cases, as is used for public reporting. It is also possible that the finding is real given that large‐volume hospitals have been demonstrated to provide better care for these conditions and are more likely to adopt systems of care that affect multiple conditions, such as electronic medical records.14, 36
The kappa scores comparing quartile of national performance for pairs of conditions were only in the fair range. There are several possible explanations for this fact: 1) outcomes for these 3 conditions are not measuring the same constructs; 2) they are all measuring the same construct, but they are unreliable in doing so; and/or 3) hospitals have similar latent quality for all 3 conditions, but the national quality of performance differs by condition, yielding variable relative performance per hospital for each condition. Based solely on our findings, we cannot distinguish which, if any, of these explanations may be true.31
Our study has several limitations. First, all 3 conditions currently publicly reported by CMS are medical diagnoses, although AMI patients may be cared for in distinct cardiology units and often undergo procedures; therefore, we cannot determine the degree to which correlations reflect hospital‐wide quality versus medicine‐wide quality. An institution may have a weak medicine department but a strong surgical department or vice versa. Second, it is possible that the correlations among conditions for readmission and among conditions for mortality are attributable to patient characteristics that are not adequately adjusted for in the risk‐adjustment model, such as socioeconomic factors, or to hospital characteristics not related to quality, such as coding practices or inter‐hospital transfer rates. For this to be true, these unmeasured characteristics would have to be consistent across different conditions within each hospital and have a consistent influence on outcomes. Third, it is possible that public reporting may have prompted disease‐specific focus on these conditions. We do not have data from non‐publicly reported conditions to test this hypothesis. Fourth, there are many small‐volume hospitals in this study; their estimates for readmission and mortality are less reliable than for large‐volume hospitals, potentially limiting our ability to detect correlations in this group of hospitals.
This study lends credence to the hypothesis that 30‐day risk‐standardized mortality and readmission rates for individual conditions may reflect aspects of hospital‐wide quality or at least medicine‐wide quality, although the correlations are not large enough to conclude that hospital‐wide factors play a dominant role, and there are other possible explanations for the correlations. Further work is warranted to better understand the causes of the correlations, and to better specify the nature of hospital factors that contribute to correlations among outcomes.
Acknowledgements
Disclosures: Dr Horwitz is supported by the National Institute on Aging (K08 AG038336) and by the American Federation of Aging Research through the Paul B. Beeson Career Development Award Program. Dr Horwitz is also a Pepper Scholar with support from the Claude D. Pepper Older Americans Independence Center at Yale University School of Medicine (P30 AG021342 NIH/NIA). Dr Krumholz is supported by grant U01 HL105270‐01 (Center for Cardiovascular Outcomes Research at Yale University) from the National Heart, Lung, and Blood Institute. Dr Krumholz chairs a cardiac scientific advisory board for UnitedHealth. Authors Drye, Krumholz, and Wang receive support from the Centers for Medicare & Medicaid Services (CMS) to develop and maintain performance measures that are used for public reporting. The analyses upon which this publication is based were performed under Contract Number HHSM‐500‐2008‐0025I Task Order T0001, entitled Measure & Instrument Development and Support (MIDS)Development and Re‐evaluation of the CMS Hospital Outcomes and Efficiency Measures, funded by the Centers for Medicare & Medicaid Services, an agency of the US Department of Health and Human Services. The Centers for Medicare & Medicaid Services reviewed and approved the use of its data for this work, and approved submission of the manuscript. The content of this publication does not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US Government. The authors assume full responsibility for the accuracy and completeness of the ideas presented.
- US Department of Health and Human Services. Hospital Compare.2011. Available at: http://www.hospitalcompare.hhs.gov. Accessed March 5, 2011.
- Early readmissions to the department of medicine as a screening tool for monitoring quality of care problems.Medicine (Baltimore).2008;87(5):294–300. , , .
- Hospital inpatient mortality. Is it a predictor of quality?N Engl J Med.1987;317(26):1674–1680. , , , , .
- Relationship between Medicare's hospital compare performance measures and mortality rates.JAMA.2006;296(22):2694–2702. , .
- Public reporting of discharge planning and rates of readmissions.N Engl J Med.2009;361(27):2637–2645. , , .
- Process of care performance measures and long‐term outcomes in patients hospitalized with heart failure.Med Care.2010;48(3):210–216. , , , et al.
- Variations in inpatient mortality among hospitals in different system types, 1995 to 2000.Med Care.2009;47(4):466–473. , , , , , .
- A systematic review and meta‐analysis of studies comparing mortality rates of private for‐profit and private not‐for‐profit hospitals.Can Med Assoc J.2002;166(11):1399–1406. , , , et al.
- What distinguishes top‐performing hospitals in acute myocardial infarction mortality rates? A qualitative study.Ann Intern Med.2011;154(6):384–390. , , , et al.
- Perceptions of hospital safety climate and incidence of readmission.Health Serv Res.2011;46(2):596–616. , , .
- Decrease in hospital‐wide mortality rate after implementation of a commercially sold computerized physician order entry system.Pediatrics.2010;126(1):14–21. , , , et al.
- The condition of the literature on differences in hospital mortality.Med Care.1989;27(4):315–336. , , .
- Threshold volumes associated with higher survival in health care: a systematic review.Med Care.2003;41(10):1129–1141. , , .
- Hospital volume and 30‐day mortality for three common medical conditions.N Engl J Med.2010;362(12):1110–1118. , , , et al.
- Patient Protection and Affordable Care Act Pub. L. No. 111–148, 124 Stat, §3025.2010. Available at: http://www.gpo.gov/fdsys/pkg/PLAW‐111publ148/content‐detail.html. Accessed on July 26, year="2012"2012.
- Are mortality rates for different operations related? Implications for measuring the quality of noncardiac surgery.Med Care.2006;44(8):774–778. , , .
- Do hospitals with low mortality rates in coronary artery bypass also perform well in valve replacement?Ann Thorac Surg.2003;76(4):1131–1137. , , , .
- Differences among hospitals in Medicare patient mortality.Health Serv Res.1989;24(1):1–31. , , , , .
- Variations in standardized hospital mortality rates for six common medical diagnoses: implications for profiling hospital quality.Med Care.1998;36(7):955–964. , , , .
- Development, validation, and results of a measure of 30‐day readmission following hospitalization for pneumonia.J Hosp Med.2011;6(3):142–150. , , , et al.
- An administrative claims measure suitable for profiling hospital performance on the basis of 30‐day all‐cause readmission rates among patients with heart failure.Circ Cardiovasc Qual Outcomes.2008;1:29–37. , , , et al.
- Quality of care for acute myocardial infarction at urban safety‐net hospitals.Health Aff (Millwood).2007;26(1):238–248. , , , et al.
- National Quality Measures Clearinghouse.2011. Available at: http://www.qualitymeasures.ahrq.gov/. Accessed February 21,year="2011"2011.
- An administrative claims model suitable for profiling hospital performance based on 30‐day mortality rates among patients with an acute myocardial infarction.Circulation.2006;113(13):1683–1692. , , , et al.
- An administrative claims model suitable for profiling hospital performance based on 30‐day mortality rates among patients with heart failure.Circulation.2006;113(13):1693–1701. , , , et al.
- An administrative claims model for profiling hospital 30‐day mortality rates for pneumonia patients.PLoS One.2011;6(4):e17401. , , , et al.
- An administrative claims measure suitable for profiling hospital performance based on 30‐day all‐cause readmission rates among patients with acute myocardial infarction.Circ Cardiovasc Qual Outcomes.2011;4(2):243–252. , , , et al.
- The application of electronic computers to factor analysis.Educ Psychol Meas.1960;20:141–151. .
- On the ‘probable error’ of a coefficient of correlation deduced from a small sample.Metron.1921;1:3–32. .
- Comparing correlated but nonoverlapping correlations.Psychol Methods.1996;1(2):178–183. , , .
- Centers for Medicare and Medicaid Services.Medicare Shared Savings Program: Accountable Care Organizations, Final Rule.Fed Reg.2011;76:67802–67990.
- Massachusetts Healthcare Quality and Cost Council. Potentially Preventable Readmissions.2011. Available at: http://www.mass.gov/hqcc/the‐hcqcc‐council/data‐submission‐information/potentially‐preventable‐readmissions‐ppr.html. Accessed February 29, 2012.
- Texas Medicaid. Potentially Preventable Readmission (PPR).2012. Available at: http://www.tmhp.com/Pages/Medicaid/Hospital_PPR.aspx. Accessed February 29, 2012.
- New York State. Potentially Preventable Readmissions.2011. Available at: http://www.health.ny.gov/regulations/recently_adopted/docs/2011–02‐23_potentially_preventable_readmissions.pdf. Accessed February 29, 2012.
- Variability in the measurement of hospital‐wide mortality rates.N Engl J Med.2010;363(26):2530–2539. , , , , .
- Use of electronic health records in U.S. hospitals.N Engl J Med.2009;360(16):1628–1638. , , , et al.
- US Department of Health and Human Services. Hospital Compare.2011. Available at: http://www.hospitalcompare.hhs.gov. Accessed March 5, 2011.
- Early readmissions to the department of medicine as a screening tool for monitoring quality of care problems.Medicine (Baltimore).2008;87(5):294–300. , , .
- Hospital inpatient mortality. Is it a predictor of quality?N Engl J Med.1987;317(26):1674–1680. , , , , .
- Relationship between Medicare's hospital compare performance measures and mortality rates.JAMA.2006;296(22):2694–2702. , .
- Public reporting of discharge planning and rates of readmissions.N Engl J Med.2009;361(27):2637–2645. , , .
- Process of care performance measures and long‐term outcomes in patients hospitalized with heart failure.Med Care.2010;48(3):210–216. , , , et al.
- Variations in inpatient mortality among hospitals in different system types, 1995 to 2000.Med Care.2009;47(4):466–473. , , , , , .
- A systematic review and meta‐analysis of studies comparing mortality rates of private for‐profit and private not‐for‐profit hospitals.Can Med Assoc J.2002;166(11):1399–1406. , , , et al.
- What distinguishes top‐performing hospitals in acute myocardial infarction mortality rates? A qualitative study.Ann Intern Med.2011;154(6):384–390. , , , et al.
- Perceptions of hospital safety climate and incidence of readmission.Health Serv Res.2011;46(2):596–616. , , .
- Decrease in hospital‐wide mortality rate after implementation of a commercially sold computerized physician order entry system.Pediatrics.2010;126(1):14–21. , , , et al.
- The condition of the literature on differences in hospital mortality.Med Care.1989;27(4):315–336. , , .
- Threshold volumes associated with higher survival in health care: a systematic review.Med Care.2003;41(10):1129–1141. , , .
- Hospital volume and 30‐day mortality for three common medical conditions.N Engl J Med.2010;362(12):1110–1118. , , , et al.
- Patient Protection and Affordable Care Act Pub. L. No. 111–148, 124 Stat, §3025.2010. Available at: http://www.gpo.gov/fdsys/pkg/PLAW‐111publ148/content‐detail.html. Accessed on July 26, year="2012"2012.
- Are mortality rates for different operations related? Implications for measuring the quality of noncardiac surgery.Med Care.2006;44(8):774–778. , , .
- Do hospitals with low mortality rates in coronary artery bypass also perform well in valve replacement?Ann Thorac Surg.2003;76(4):1131–1137. , , , .
- Differences among hospitals in Medicare patient mortality.Health Serv Res.1989;24(1):1–31. , , , , .
- Variations in standardized hospital mortality rates for six common medical diagnoses: implications for profiling hospital quality.Med Care.1998;36(7):955–964. , , , .
- Development, validation, and results of a measure of 30‐day readmission following hospitalization for pneumonia.J Hosp Med.2011;6(3):142–150. , , , et al.
- An administrative claims measure suitable for profiling hospital performance on the basis of 30‐day all‐cause readmission rates among patients with heart failure.Circ Cardiovasc Qual Outcomes.2008;1:29–37. , , , et al.
- Quality of care for acute myocardial infarction at urban safety‐net hospitals.Health Aff (Millwood).2007;26(1):238–248. , , , et al.
- National Quality Measures Clearinghouse.2011. Available at: http://www.qualitymeasures.ahrq.gov/. Accessed February 21,year="2011"2011.
- An administrative claims model suitable for profiling hospital performance based on 30‐day mortality rates among patients with an acute myocardial infarction.Circulation.2006;113(13):1683–1692. , , , et al.
- An administrative claims model suitable for profiling hospital performance based on 30‐day mortality rates among patients with heart failure.Circulation.2006;113(13):1693–1701. , , , et al.
- An administrative claims model for profiling hospital 30‐day mortality rates for pneumonia patients.PLoS One.2011;6(4):e17401. , , , et al.
- An administrative claims measure suitable for profiling hospital performance based on 30‐day all‐cause readmission rates among patients with acute myocardial infarction.Circ Cardiovasc Qual Outcomes.2011;4(2):243–252. , , , et al.
- The application of electronic computers to factor analysis.Educ Psychol Meas.1960;20:141–151. .
- On the ‘probable error’ of a coefficient of correlation deduced from a small sample.Metron.1921;1:3–32. .
- Comparing correlated but nonoverlapping correlations.Psychol Methods.1996;1(2):178–183. , , .
- Centers for Medicare and Medicaid Services.Medicare Shared Savings Program: Accountable Care Organizations, Final Rule.Fed Reg.2011;76:67802–67990.
- Massachusetts Healthcare Quality and Cost Council. Potentially Preventable Readmissions.2011. Available at: http://www.mass.gov/hqcc/the‐hcqcc‐council/data‐submission‐information/potentially‐preventable‐readmissions‐ppr.html. Accessed February 29, 2012.
- Texas Medicaid. Potentially Preventable Readmission (PPR).2012. Available at: http://www.tmhp.com/Pages/Medicaid/Hospital_PPR.aspx. Accessed February 29, 2012.
- New York State. Potentially Preventable Readmissions.2011. Available at: http://www.health.ny.gov/regulations/recently_adopted/docs/2011–02‐23_potentially_preventable_readmissions.pdf. Accessed February 29, 2012.
- Variability in the measurement of hospital‐wide mortality rates.N Engl J Med.2010;363(26):2530–2539. , , , , .
- Use of electronic health records in U.S. hospitals.N Engl J Med.2009;360(16):1628–1638. , , , et al.
Copyright © 2012 Society of Hospital Medicine
Interdisciplinary Hospital QI Teams
Interest in healthcare teams has surged in recent years. A majority of the interest has been devoted to teamwork in the interdisciplinary clinical teams that staff operating rooms,1 emergency departments,2 and other inpatient settings.3 Interventions that enhance elements of teamwork like communication, mutual support among team members, and leadership have demonstrated effectiveness.4
Less attention has been paid to improving the success of hospital quality improvement (QI) teams, which gather individuals from different disciplines to improve a defined aspect of care. Studies suggest that QI teams can enable transformational change in healthcare systems,57 and that interdisciplinary representation,8, 9 physician involvement,10, 11 and clear goals12, 13 are associated with successful QI efforts. However, few studies have examined the behaviors of the QI teams that planned and implemented these efforts. Understanding how QI teams work to achieve their goals will allow hospitals to encourage these behaviors, and allow researchers to design interventions to augment these behaviors.
Accordingly, we sought to characterize the behaviors of successful interdisciplinary hospital QI teams. We previously reported on the strategies used by hospitals to reduce door‐to‐balloon times for patients with ST‐elevation myocardial infarction (STEMI)14, 15 to the evidence‐based guideline of 90 minutes.16 Our objective is to examine how QI teams designed and implemented these strategies. We believe that studying high‐performing QI teams is a first step to developing testable hypotheses about the effectiveness of QI team behaviors and mechanisms by which these behaviors might produce positive team outcomes.
METHODS
We designed a qualitative study using in‐depth interviews. We selected a qualitative methodology, since behaviors, social norms, and interpersonal interactions can be most appropriately examined using qualitative methods.17, 18 In addition, we used a positive deviance approach,19 where we focused on hospitals with top performance and the most improvement in door‐to‐balloon times. We sampled from hospitals in the National Registry of Myocardial Infarction (NRMI) who perform percutaneous coronary intervention (PCI, n = 151). We selected hospitals whose median door‐to‐balloon times were 90 minutes (n = 35). Then, we ranked hospitals in descending order according to their improvement during the previous 3 years (19992002). We sampled hospitals in descending order until we reached theoretical saturation where, as recommended for qualitative inquiry,2022 additional site visits did not uncover new concepts or patterns regarding our study questions. All sampled hospitals agreed to participate.
The first contact at each hospital was typically the director of QI. We asked to interview anyone with substantial involvement in the effort to reduce door‐to‐balloon times, and suggested that a wide variety of disciplines and roles be represented. We also used the snowball technique,22 where we asked participants to provide the names of individuals with substantial involvement in the reducing door‐to‐balloon times. Participants had varied levels of participation in QI teams. We purposely asked for minority and dissenting views from all participants.
At least 2 members of the research team conducted in‐depth interviews during hospital site visits. Interviews were conducted individually or in small groups, and lasted 1 to 1.5 hours. All data were audiotaped after verbal consent. Our interviews began with the grand tour question: What, if anything, has this hospital done to reduce its door‐to‐balloon times for patients with STEMI? The research team used standardized probes20, 23 to guide the discussion and achieve a complete understanding of the phenomena under study, including leadership and activities of the QI teams, and recommendations to other hospitals that wished to reduce door‐to‐balloon times. As recommended by experts,23 our interview guide was purposefully open‐ended to capture the range of experiences with QI teams. We did not specifically probe for facilitating or challenging behaviors. Audiotapes were transcribed by an independent, professional transcriptionist.
For this analysis, we defined QI teams as groups of administrators, providers, and staff who designed, implemented, and monitored processes to reduce door‐to‐balloon times. Each analysis team member independently cataloged quotes about team behaviors using a list of concepts (or codes). We then analyzed the quotes to identify recurrent themes relevant to the behaviors of interdisciplinary QI teams. We used the constant comparative method of analysis,20, 24, 25 which stipulates that the initial list of codes is refined as new transcripts are analyzed, and the final list is applied to all the transcripts. The analysis team included experts in QI, medicine, qualitative and health services research, as well as organizational psychology, and one of the interviewers. The presence of diverse perspectives in the analysis team,21 and a detailed audit trail20 to document the emergence of codes and themes, helped enhance researcher neutrality, data accuracy, and validity. We used Atlas.ti version 5.2 (Scientific Software Development GMbH, Berlin, Germany) to assist in the analysis.
RESULTS
Our sample (n = 11) included hospitals that varied on several characteristics (eg, geographic location), and median door‐to‐balloon times ranged from 55.5 to 89.5 minutes (Table 1). Hospitals in our sample had higher mean improvements in door‐to‐balloon times compared with non‐sampled NRMI hospitals (n = 140, 24 minutes vs 3 minutes over 3 years). Our interview participants (n = 122) included physicians, nurses, QI personnel, and administrative staff (Table 2). Five behaviors emerged from the data analysis. We found that interdisciplinary QI teams in successful hospitals focused on: (1) motivating involved hospital staff towards a shared goal, (2) creating opportunities for learning and problem‐solving, (3) addressing the impact of changes in care processes on staff, (4) protecting the integrity of the newly developed care processes, and (5) representing each involved clinical discipline effectively. These behaviors were recurrent across our diverse set of hospitals.
Hospital | Region | Teaching Status | No. of Beds | STEMI Annualized Volume* | Median Door‐to‐Balloon Time (min) |
---|---|---|---|---|---|
| |||||
1 | Northeast | Yes | 770 | 68 | 85.5 |
2 | Midwest | Yes | 176 | 33 | 75.5 |
3 | South | Yes | 870 | 187 | 55.5 |
4 | Midwest | Yes | 426 | 85 | 70.5 |
5 | South | No | 350 | 94 | 69.0 |
6 | West | Yes | 204 | 89 | 82.0 |
7 | West | Yes | 277 | 41 | 89.0 |
8 | South | Yes | 633 | 124 | 86.5 |
9 | West | No | 190 | 43 | 89.5 |
10 | West | No | 111 | 51 | 87.0 |
11 | Midwest | Yes | 276 | 95 | 87.0 |
Participants | No. in Sample (n = 122) |
---|---|
| |
Cardiology | |
MD | 20 |
Nurse | 15 |
Emergency Medicine | |
MD | 15 |
Nurse | 9 |
EMS | 3 |
Executive managers | 20 |
QI personnel | 17 |
Other nurses | 13 |
Other clinical/support staff | 10 |
Motivating Involved Hospital Staff Toward a Shared Goal
As with any team, the QI teams in our sample had to motivate others in order to be successful:
Making certain that we have common goals [and] figuring out the best way to get there. It has to be a team, a partnership. It can't be I'm better than you, or this discipline is better than that discipline. We're all here for one reason. Hospital #11, Administrator
To redesign the door‐to‐balloon care process, successful QI teams engaged clinical disciplines that felt disempowered previously:
[ED physicians] were receptive, but they said, Cardiology won't let us do this. It's not going to be [just] cardiology anymore; it has to be everybody, because we really need to improve this time. Hospital #7, QI personnel
Teams also promoted reduction in door‐to‐balloon times as a goal that required shared participation from clinical disciplines including cardiology and emergency medicine, but also laboratory medicine, critical care, pharmacy, and transport. Achieving this goal would positively impact institutional standing:
When people get entrenched in their little domes they have a hard time seeing the overall benefit. Stress the institutional importance of this issue and the importance of cooperation and how it translates to better patient outcomes. [This is what] we're being monitored on; a very clear way in which we can be judged. Hospital #7, Catheterization Lab Medical Director
Creating Opportunities for Learning and Problem‐Solving
The work of these QI teams resulted in interdisciplinary conflict, but when individuals voiced frustration with other disciplines, it was seen as a necessary step in the redesign of a complex, interdisciplinary care process:
The first 6 to 8 months were spent team building and dealing with the vying for control. It was a total waste of time but necessary because now it was an interdisciplinary thing. It wasn't something we were trying to change within one service. We were asking everyone to sit down and agree about what they were going to do. The first [meetings] were shouting matches. The ED was becoming a scapegoat; the problem was never in the cath lab. We were able to act on some of those issues. You need to see both sides and understand what the barriers are. Hospital #1, Cardiology Nurse
Although challenging, interdisciplinary QI teams allowed team members to gain the detailed knowledge about front‐line operations that they needed:
We cardiologists don't really deal with what is happening behind the scenesexactly what a unit clerk does, and where the bottlenecks are. I discovered that lots of ideas come from unexpected places. Hospital #11, Cardiologist
To facilitate learning, teams cultivated a nonjudgmental, mutual trust atmosphere:
Throughout the whole process, there's been a lot of dialogue. Everybody throws their assumptions on the table, assumptions are respected; there is a lot of open communication. Hospital #3, Cardiology QI personnel
In addition, reducing door‐to‐balloon times required iterative problem‐solving. QI teams in our sample welcomed opportunities to learn from less effective strategies:
I'm one that's never too upset to ditch something if something was working and you switched to something else and now it's not working. You tried it. Go back. Or maybe it needs to be fine tuned. Hospital #1, Administrator
Addressing the Impact of Changes in Care Processes on Staff
Many hospitals in our sample required staff to arrive at the catheterization lab within 2030 minutes of being paged. This resulted in more demanding call schedules and changing roles (eg, activation of the cath lab by emergency department [ED] physicians instead of cardiologists). Participants conveyed both the burden of, and the satisfaction with, new processes:
It is a tremendous commitment time‐wise. We had a first call schedule but had to go to a second call schedule. There's no way you can get around the fact that it's very disruptive to your life. You're sitting down to dinner and suddenly you've got to go, and you don't have a chance to kiss the kids goodbye. You're out the door and heading to the hospital. It's been very disruptive, but it's a good program. No one regrets it. Hospital #5, Cardiologist
Successful QI teams validated staff concerns about the impact of these changes on workflow and quality of life:
We have few people who are nay saying for the sake of nay saying. People have legitimate concerns. I value those concerns as they affect the people who are involved. Hospital #4, Cardiologist
Teams responded to these concerns by testing solutions and eliminating negative consequences where possible:
[ED said]: We're uncomfortable with being the ordering physicians for labs drawn after patients leave the ED. I said, Let's make that issue go away. If they perceive it as a risk, let's make that fear go away because that removes a barrier. Hospital #4, Cardiologist
Protecting the Integrity of the New Care Processes
Once the necessary changes to the care of patients with STEMI were in place, these teams ensured that new processes were followed consistently. Rather than allowing customization of the processes by front‐line staff, QI teams monitored cases, gathered feedback, and made necessary modifications. Small modifications to the protocols helped incorporate front‐line feedback and reinvigorate staff:
People got comfortable and slower, and I quit hassling the group. We reinvigorated the Emergency Room, met with them, and changed the process a little bit. Change always perks people's attention. Hospital #8, Cardiologist
Another strategy to protect the integrity of the redesigned process was to highlight its value by publicizing clinical successes:
[We] let them know what we found and how the patient is doing. It's a pat on the back saying you did a good job. Next time [the ED physicians] will be screening that much closer. When we're leaving the hospital at 3 a.m. they'll say How did it go? They want to know; that adds to that team feeling because everybody is important. They help us do our job and we help them do theirs. Hospital #9, Catheterization Lab Technologist
Lastly, QI teams empowered front‐line staff to comply with the new process by emphasizing benefit to patients. This allowed staff to overcome hierarchical boundaries:
ED staff told us that sometimes patients waited because the cardiologist was getting a history and physical. They've been empowered to say We're ready to go. Before nurses felt that they couldn't really do that. Now we're getting through to them that time is muscle and that guy is costing the patient. Hospital #5, QI personnel
Representing Each Involved Clinical Discipline Effectively
Participants remarked on the importance of team member selection. Successful QI teams had members who could effectively represent each involved discipline. Effective representation involved in‐depth knowledge of one's aspect of the care process and communicating that perspective to the team:
The lab director got together with the ED director, who got together with the radiology director, who asked Who's transporting the patient?; How are we going to get blood drawn, what's going to happen? That middle management team became critical. Hospital #10, Administrator
Effective representation also required the authority to endorse and implement necessary changes:
The people that head councils are not people in the position to make changes in the workflow of the hospital. For example, having the ED doctor activate the cath lab. You'd say Well, the Chairman of Medicine would probably have something to do with this. Wrong. The Chairman of Medicine has no interest in STEMI care. Go to the Chairman of Cardiology. Sounds good, but you have to talk to the interventional guys. Go to the head of the cath lab. Sounds good, but it really has to go to a cath lab committee meeting. Hospital #1, QI personnel
In addition to knowledge of processes and authority to implement changes, team members in these successful QI teams had to be proficient in disseminating information on performance and changes to processes. Teams developed regular communication channels across levels of the hospital hierarchy, from front‐line staff to executive management:
Communication, communication, communication. Make sure you have a system set up where there's opportunity for back and forth between all the different levels. Set up the infrastructure from the beginning where there's a mechanism to relay information up and down. Hospital #1, Cardiology Nurse
Discussion
We identified 5 behaviors of successful interdisciplinary QI teams based on our analysis of hospitals that reduced door‐to‐balloon times for patients with STEMI. These QI teams: (1) motivated involved hospital staff to consider lowering door‐to‐balloon times, a shared goal, (2) created opportunities for learning and problem‐solving, (3) addressed the impact of changes to care processes for patients with STEMI on staff, (4) protected the integrity of new care processes, and (5) represented each clinical discipline effectively by having members with in‐depth knowledge and authority.
Experts suggest that the key elements of effective teamwork in healthcare include prioritizing team over individual goals, mutual understanding, leadership, adaptability, and anticipation of the needs of others.26 These elements are supported by mutual trust and closed‐loop communication. The behaviors of QI teams in our study represent adaptive responses to the unique demands of QI in a complex organization. These teams went beyond an improvement model of identifying and analyzing a problem, and then developing and testing solutions by: (1) motivating and gathering information from each discipline, regardless of interdisciplinary conflicts; (2) responding to the concerns of front‐line staff, while maintaining control over the improvement process; and (3) sharing information across the hospital hierarchy. Table 3 illustrates potential relationships between the team behaviors in our data, the demands on hospital QI teams, and known elements of effective teamwork.
Demands on Hospital QI TeamsWhat QI Teams Must Do to Improve Care | Elements of Teamwork* | Behaviors of QI Teams in Our Study | Examples |
---|---|---|---|
| |||
Gather information from and motivate each involved discipline | Team rather than individual goals | Motivating all involved hospital staff towards a shared goal | Promote parity among disciplines |
Invite every involved discipline | |||
Emphasize benefit to patients | |||
Gather information from and motivate each involved discipline | Mutual understanding | Creating opportunities for learning | Allow for interdisciplinary disagreements |
Gather detailed operational knowledge in a mutual‐trust environment | |||
Guide changes using objective data | |||
Respond to the concerns of front‐line staff while maintaining control over the improvement process | Anticipate the needs of others | Addressing the impact of changes on staff | Validate concerns from all disciplines |
Test solutions to negative consequences (eg, call schedules, laboratory forms) | |||
Respond to the concerns of front‐line staff while maintaining control over the improvement process | Adaptability | Protecting the integrity of new protocols | Monitor data and respond to performance losses |
Document and publicize successes | |||
Empower front‐line staff to respond to lapses in protocol | |||
Keep all levels of the hospital hierarchy informed during he improvement process | Leadership | Representing each involved clinical discipline effectively | Select members with in‐depth knowledge about processes |
Select members with authority to implement changes within their discipline | |||
Exchange information with executive management and front‐line staff |
The behaviors in our study suggest effective teamwork strategies for QI. For example, our data suggest that successful interdisciplinary QI teams need effective representation from each involved discipline. This representation is necessary for motivation of front‐line staff, gathering of detailed information about processes, and the effective implementation of changes. Although this level of representation might challenge the cohesiveness of some teams,27 the teams in our sample managed conflict among disciplines without sacrificing the shared goal. By allocating attention and resources to the concerns of each discipline, the teams we studied prioritized team over individual goals and promoted mutual understanding.
Similarly, deciding when to modify the new protocols required leadership, adaptability, and anticipation of the needs of others. Successful QI teams in our sample modified protocols based on data and feedback, and created the mutual trust environment that is known to facilitate learning among disciplines.2830 Their willingness to learn, however, did not deter teams from protecting the integrity of new protocols. Lastly, participants stressed the importance of managing information across hierarchical boundaries. Managing reliable, timely, and accurate information across all levels is crucial to teamwork, and to the power and influence of a team.31
Our conclusions should be interpreted in light of several limitations. First, our study did not include a comparison group of low‐performing hospitals. We followed the recommendations of qualitative research experts23 who recommend sampling those with the most information on, and experience with, the phenomena under study (QI teams in high‐performing hospitals). The hypotheses we present here require further testing in quantitative studies of hospitals with diversity in QI team outcomes. Second, it is possible that sampled participants favored responses that they considered more desirable. To minimize this bias, we interviewed multiple participants per hospital, assured their confidentiality, and asked them to elaborate their responses. We sampled participants with a wide range of clinical and operational roles in each hospital, and also used the snowball sampling method to augment our sample. The range of responses collected, including frank discussions about setbacks, argues against the existence of contrasting behaviors to those captured. Third, although our sample included hospitals of various size and location, our findings might not reflect those of a larger sample of US hospitals. Last, the behaviors of QI teams may differ for other clinical processes.
Translating these findings into practice will require future studies of the impact of QI team behaviors on sustainability of quality gains. Since QI teams are not typically permanent, additional research is needed to identify behaviors associated with sustainable improvements. In addition, we must test whether the relationship between behaviors and team outcomes depends on whether the QI team strives to reach an evidence‐based goal or to improve a process as much as possible. Our sample demonstrated a combined approach, where the evidence‐based goal was followed by a desire to continue to further reduce door‐to‐balloon times. Similarly, the relationship between behaviors and team outcomes might depend on the catalyst for improvement (eg, regulatory pressure, an adverse event). The confluence of strong evidence and regulatory pressure that fueled these teams might not be true for other measures. Lastly, studies of teamwork in QI teams will require objective measures of team behaviors. A combination of surveys and direct team observation will likely be required to measure these behaviors, especially effective representation.
Our study highlights behaviors common to successful interdisciplinary QI teams in high‐performing hospitals. Previous studies have identified elements of teamwork and the importance of teams to QI, but have not examined team behaviors. In the era of an ever‐growing list of quality measures and of movement toward performance‐based reimbursement models,3234 hospitals have embraced the use of interdisciplinary teams as a key component of QI efforts. Our findings suggest that hospitals could enhance QI team effectiveness by promoting behaviors associated with successful interdisciplinary teams. When applied to QI teams, teamwork training could be supplemented with knowledge, attitudes, and skills regarding information‐gathering, problem‐solving, and communication across disciplines and levels of the hospital hierarchy.
Acknowledgements
The authors thank Harlan Krumholz for his mentorship; Tashonna Webster, Emily Cherlin, and Jeph Herrin for technical support; also the RWJ Clinical Scholars Program, Montefiore's DGIM faculty, and the participants of this study.
- The efficacy of medical team training: improved team performance and decreased operating room delays.Ann Surg.2010;252:477–485. , , .
- Error reduction and performance improvement in the Emergency Department through formal teamwork training: evaluation results of the MedTeams project.Health Serv Res.2002;37:1553–1581. , , , et al.
- Interventions to improve team effectiveness: a systematic review.Health Policy.2010;94:183–195. , , , .
- The anatomy of health care team training and the state of practice: a critical review.Acad Med. doi: 10.1097/ACM.0b013e3181f2e907 [published Online First: Sep 21, 2010]. , , , et al.
- Microsystems in health care: part 1. Learning from high‐performing front‐line clinical units.Jt Comm J Qual Saf.2002;28:472–493. , , , et al.
- Organizational factors associated with high performance in quality and safety in academic medical centers.Acad Med.2007;82:1178–1186. , , , , , .
- Transformational change in health care systems: an organizational model.Health Care Manage Rev.2007;32:309–320. , , , et al.
- Treatment teams that work (and those that don't): an application of Hackman's group effectiveness model to interdisciplinary teams in psychiatric hospitals.J Appl Behav Sci.1995;31:303–327. .
- What do we know about health care team effectiveness? A review of the literature.Med Care Res Rev.2006;63:263–300. , .
- Understanding team‐based quality improvement for depression in primary care.Health Serv Res.2002;37:1009–1029. , , , et al.
- The role of perceived team effectiveness in improving chronic illness care.Med Care.2004;42:1040–1048. , , , et al.
- The determinants of effectiveness in primary health care teams.J Interprof Care.1999;13:7–18. , .
- Characteristics of successful quality improvement teams: lessons from five collaborative projects in the VHA.Jt Comm J Qual Saf.2004;30:152–162. , .
- Achieving door‐to‐balloon times that meet quality guidelines: how do successful hospitals do it?J Am Coll Cardiol.2005;46:1236–1241. , , , et al.
- Achieving rapid door‐to‐balloon times: how top hospitals improve complex clinical systems.Circulation.2006;113:1079–1085. , , , et al.
- ACC/AHA guidelines for the management of patients with ST‐elevation myocardial infarction: a report of the ACC/AHA Task Force on Practice Guidelines (Committee to Revise the 1999 Guidelines on the Management of Patients with Acute Myocardial Infarction).Circulation.2004;110:e82–e293. , , , et al.
- Reaching the parts other methods cannot reach: an introduction to qualitative methods in health and health services research.BMJ.1995;311:42–45. , .
- Qualitative and mixed methods provide unique contributions to outcomes research.Circulation.2009;119:1442–1452. , , .
- Research in action: using positive deviance to improve quality of health care.Implement Sci.2009;4:25. doi: 10.1186/1748–5908‐4–25 [published Online First: May 8, 2009]. , , , , , .
- Miles MB, Huberman AM, eds.Qualitative Data Analysis: An Expanded Sourcebook.Thousand Oaks, CA:Sage,1994.
- Crabtree BF, Miller WL, eds.Doing Qualitative Research.London:Sage,1999.
- Qualitative research in health care: assessing quality in qualitative research.BMJ.2000;320:50–52. , .
- Qualitative Research 42:1758–1772. .
- Discovery of Grounded Theory.Chicago, IL:Aldine,1967. , .
- Does team training work? Principles for health care.Acad Emerg Med.2008;15:1002–1009. , , , .
- Senior executive teams: not what you think.Consult Psychol J Pract Res.2005;57:107–117. .
- Psychological safety and learning behavior in work teams.Admin Sci Q.1999;44:350–383. .
- Making it safe: the effects of leader inclusiveness and professional status on psychological safety and improvement efforts in health care teams.J Organiz Behav.2006;27:941–966. , .
- Learning from preventable adverse events in health care organizations: development of a multilevel model of learning and propositions.Health Care Manage Rev.2007;32:330–340. , , .
- Managing with Power: Politics and Influence in Organizations.Boston, MA:Harvard Business School Press,1993:111–125. .
- Using Medicare payment policy to transform the health system: a framework for improving performance.Health Aff.2009;28:w238–w250. , , , .
- Value‐driven health care: implications for hospitals and hospitalists.J Hosp Med.2009;4:507–511. .
- Medicare program: hospital inpatient value‐based purchasing program, proposed rule.Fed Reg.76(9):2454–2491.
Interest in healthcare teams has surged in recent years. A majority of the interest has been devoted to teamwork in the interdisciplinary clinical teams that staff operating rooms,1 emergency departments,2 and other inpatient settings.3 Interventions that enhance elements of teamwork like communication, mutual support among team members, and leadership have demonstrated effectiveness.4
Less attention has been paid to improving the success of hospital quality improvement (QI) teams, which gather individuals from different disciplines to improve a defined aspect of care. Studies suggest that QI teams can enable transformational change in healthcare systems,57 and that interdisciplinary representation,8, 9 physician involvement,10, 11 and clear goals12, 13 are associated with successful QI efforts. However, few studies have examined the behaviors of the QI teams that planned and implemented these efforts. Understanding how QI teams work to achieve their goals will allow hospitals to encourage these behaviors, and allow researchers to design interventions to augment these behaviors.
Accordingly, we sought to characterize the behaviors of successful interdisciplinary hospital QI teams. We previously reported on the strategies used by hospitals to reduce door‐to‐balloon times for patients with ST‐elevation myocardial infarction (STEMI)14, 15 to the evidence‐based guideline of 90 minutes.16 Our objective is to examine how QI teams designed and implemented these strategies. We believe that studying high‐performing QI teams is a first step to developing testable hypotheses about the effectiveness of QI team behaviors and mechanisms by which these behaviors might produce positive team outcomes.
METHODS
We designed a qualitative study using in‐depth interviews. We selected a qualitative methodology, since behaviors, social norms, and interpersonal interactions can be most appropriately examined using qualitative methods.17, 18 In addition, we used a positive deviance approach,19 where we focused on hospitals with top performance and the most improvement in door‐to‐balloon times. We sampled from hospitals in the National Registry of Myocardial Infarction (NRMI) who perform percutaneous coronary intervention (PCI, n = 151). We selected hospitals whose median door‐to‐balloon times were 90 minutes (n = 35). Then, we ranked hospitals in descending order according to their improvement during the previous 3 years (19992002). We sampled hospitals in descending order until we reached theoretical saturation where, as recommended for qualitative inquiry,2022 additional site visits did not uncover new concepts or patterns regarding our study questions. All sampled hospitals agreed to participate.
The first contact at each hospital was typically the director of QI. We asked to interview anyone with substantial involvement in the effort to reduce door‐to‐balloon times, and suggested that a wide variety of disciplines and roles be represented. We also used the snowball technique,22 where we asked participants to provide the names of individuals with substantial involvement in the reducing door‐to‐balloon times. Participants had varied levels of participation in QI teams. We purposely asked for minority and dissenting views from all participants.
At least 2 members of the research team conducted in‐depth interviews during hospital site visits. Interviews were conducted individually or in small groups, and lasted 1 to 1.5 hours. All data were audiotaped after verbal consent. Our interviews began with the grand tour question: What, if anything, has this hospital done to reduce its door‐to‐balloon times for patients with STEMI? The research team used standardized probes20, 23 to guide the discussion and achieve a complete understanding of the phenomena under study, including leadership and activities of the QI teams, and recommendations to other hospitals that wished to reduce door‐to‐balloon times. As recommended by experts,23 our interview guide was purposefully open‐ended to capture the range of experiences with QI teams. We did not specifically probe for facilitating or challenging behaviors. Audiotapes were transcribed by an independent, professional transcriptionist.
For this analysis, we defined QI teams as groups of administrators, providers, and staff who designed, implemented, and monitored processes to reduce door‐to‐balloon times. Each analysis team member independently cataloged quotes about team behaviors using a list of concepts (or codes). We then analyzed the quotes to identify recurrent themes relevant to the behaviors of interdisciplinary QI teams. We used the constant comparative method of analysis,20, 24, 25 which stipulates that the initial list of codes is refined as new transcripts are analyzed, and the final list is applied to all the transcripts. The analysis team included experts in QI, medicine, qualitative and health services research, as well as organizational psychology, and one of the interviewers. The presence of diverse perspectives in the analysis team,21 and a detailed audit trail20 to document the emergence of codes and themes, helped enhance researcher neutrality, data accuracy, and validity. We used Atlas.ti version 5.2 (Scientific Software Development GMbH, Berlin, Germany) to assist in the analysis.
RESULTS
Our sample (n = 11) included hospitals that varied on several characteristics (eg, geographic location), and median door‐to‐balloon times ranged from 55.5 to 89.5 minutes (Table 1). Hospitals in our sample had higher mean improvements in door‐to‐balloon times compared with non‐sampled NRMI hospitals (n = 140, 24 minutes vs 3 minutes over 3 years). Our interview participants (n = 122) included physicians, nurses, QI personnel, and administrative staff (Table 2). Five behaviors emerged from the data analysis. We found that interdisciplinary QI teams in successful hospitals focused on: (1) motivating involved hospital staff towards a shared goal, (2) creating opportunities for learning and problem‐solving, (3) addressing the impact of changes in care processes on staff, (4) protecting the integrity of the newly developed care processes, and (5) representing each involved clinical discipline effectively. These behaviors were recurrent across our diverse set of hospitals.
Hospital | Region | Teaching Status | No. of Beds | STEMI Annualized Volume* | Median Door‐to‐Balloon Time (min) |
---|---|---|---|---|---|
| |||||
1 | Northeast | Yes | 770 | 68 | 85.5 |
2 | Midwest | Yes | 176 | 33 | 75.5 |
3 | South | Yes | 870 | 187 | 55.5 |
4 | Midwest | Yes | 426 | 85 | 70.5 |
5 | South | No | 350 | 94 | 69.0 |
6 | West | Yes | 204 | 89 | 82.0 |
7 | West | Yes | 277 | 41 | 89.0 |
8 | South | Yes | 633 | 124 | 86.5 |
9 | West | No | 190 | 43 | 89.5 |
10 | West | No | 111 | 51 | 87.0 |
11 | Midwest | Yes | 276 | 95 | 87.0 |
Participants | No. in Sample (n = 122) |
---|---|
| |
Cardiology | |
MD | 20 |
Nurse | 15 |
Emergency Medicine | |
MD | 15 |
Nurse | 9 |
EMS | 3 |
Executive managers | 20 |
QI personnel | 17 |
Other nurses | 13 |
Other clinical/support staff | 10 |
Motivating Involved Hospital Staff Toward a Shared Goal
As with any team, the QI teams in our sample had to motivate others in order to be successful:
Making certain that we have common goals [and] figuring out the best way to get there. It has to be a team, a partnership. It can't be I'm better than you, or this discipline is better than that discipline. We're all here for one reason. Hospital #11, Administrator
To redesign the door‐to‐balloon care process, successful QI teams engaged clinical disciplines that felt disempowered previously:
[ED physicians] were receptive, but they said, Cardiology won't let us do this. It's not going to be [just] cardiology anymore; it has to be everybody, because we really need to improve this time. Hospital #7, QI personnel
Teams also promoted reduction in door‐to‐balloon times as a goal that required shared participation from clinical disciplines including cardiology and emergency medicine, but also laboratory medicine, critical care, pharmacy, and transport. Achieving this goal would positively impact institutional standing:
When people get entrenched in their little domes they have a hard time seeing the overall benefit. Stress the institutional importance of this issue and the importance of cooperation and how it translates to better patient outcomes. [This is what] we're being monitored on; a very clear way in which we can be judged. Hospital #7, Catheterization Lab Medical Director
Creating Opportunities for Learning and Problem‐Solving
The work of these QI teams resulted in interdisciplinary conflict, but when individuals voiced frustration with other disciplines, it was seen as a necessary step in the redesign of a complex, interdisciplinary care process:
The first 6 to 8 months were spent team building and dealing with the vying for control. It was a total waste of time but necessary because now it was an interdisciplinary thing. It wasn't something we were trying to change within one service. We were asking everyone to sit down and agree about what they were going to do. The first [meetings] were shouting matches. The ED was becoming a scapegoat; the problem was never in the cath lab. We were able to act on some of those issues. You need to see both sides and understand what the barriers are. Hospital #1, Cardiology Nurse
Although challenging, interdisciplinary QI teams allowed team members to gain the detailed knowledge about front‐line operations that they needed:
We cardiologists don't really deal with what is happening behind the scenesexactly what a unit clerk does, and where the bottlenecks are. I discovered that lots of ideas come from unexpected places. Hospital #11, Cardiologist
To facilitate learning, teams cultivated a nonjudgmental, mutual trust atmosphere:
Throughout the whole process, there's been a lot of dialogue. Everybody throws their assumptions on the table, assumptions are respected; there is a lot of open communication. Hospital #3, Cardiology QI personnel
In addition, reducing door‐to‐balloon times required iterative problem‐solving. QI teams in our sample welcomed opportunities to learn from less effective strategies:
I'm one that's never too upset to ditch something if something was working and you switched to something else and now it's not working. You tried it. Go back. Or maybe it needs to be fine tuned. Hospital #1, Administrator
Addressing the Impact of Changes in Care Processes on Staff
Many hospitals in our sample required staff to arrive at the catheterization lab within 2030 minutes of being paged. This resulted in more demanding call schedules and changing roles (eg, activation of the cath lab by emergency department [ED] physicians instead of cardiologists). Participants conveyed both the burden of, and the satisfaction with, new processes:
It is a tremendous commitment time‐wise. We had a first call schedule but had to go to a second call schedule. There's no way you can get around the fact that it's very disruptive to your life. You're sitting down to dinner and suddenly you've got to go, and you don't have a chance to kiss the kids goodbye. You're out the door and heading to the hospital. It's been very disruptive, but it's a good program. No one regrets it. Hospital #5, Cardiologist
Successful QI teams validated staff concerns about the impact of these changes on workflow and quality of life:
We have few people who are nay saying for the sake of nay saying. People have legitimate concerns. I value those concerns as they affect the people who are involved. Hospital #4, Cardiologist
Teams responded to these concerns by testing solutions and eliminating negative consequences where possible:
[ED said]: We're uncomfortable with being the ordering physicians for labs drawn after patients leave the ED. I said, Let's make that issue go away. If they perceive it as a risk, let's make that fear go away because that removes a barrier. Hospital #4, Cardiologist
Protecting the Integrity of the New Care Processes
Once the necessary changes to the care of patients with STEMI were in place, these teams ensured that new processes were followed consistently. Rather than allowing customization of the processes by front‐line staff, QI teams monitored cases, gathered feedback, and made necessary modifications. Small modifications to the protocols helped incorporate front‐line feedback and reinvigorate staff:
People got comfortable and slower, and I quit hassling the group. We reinvigorated the Emergency Room, met with them, and changed the process a little bit. Change always perks people's attention. Hospital #8, Cardiologist
Another strategy to protect the integrity of the redesigned process was to highlight its value by publicizing clinical successes:
[We] let them know what we found and how the patient is doing. It's a pat on the back saying you did a good job. Next time [the ED physicians] will be screening that much closer. When we're leaving the hospital at 3 a.m. they'll say How did it go? They want to know; that adds to that team feeling because everybody is important. They help us do our job and we help them do theirs. Hospital #9, Catheterization Lab Technologist
Lastly, QI teams empowered front‐line staff to comply with the new process by emphasizing benefit to patients. This allowed staff to overcome hierarchical boundaries:
ED staff told us that sometimes patients waited because the cardiologist was getting a history and physical. They've been empowered to say We're ready to go. Before nurses felt that they couldn't really do that. Now we're getting through to them that time is muscle and that guy is costing the patient. Hospital #5, QI personnel
Representing Each Involved Clinical Discipline Effectively
Participants remarked on the importance of team member selection. Successful QI teams had members who could effectively represent each involved discipline. Effective representation involved in‐depth knowledge of one's aspect of the care process and communicating that perspective to the team:
The lab director got together with the ED director, who got together with the radiology director, who asked Who's transporting the patient?; How are we going to get blood drawn, what's going to happen? That middle management team became critical. Hospital #10, Administrator
Effective representation also required the authority to endorse and implement necessary changes:
The people that head councils are not people in the position to make changes in the workflow of the hospital. For example, having the ED doctor activate the cath lab. You'd say Well, the Chairman of Medicine would probably have something to do with this. Wrong. The Chairman of Medicine has no interest in STEMI care. Go to the Chairman of Cardiology. Sounds good, but you have to talk to the interventional guys. Go to the head of the cath lab. Sounds good, but it really has to go to a cath lab committee meeting. Hospital #1, QI personnel
In addition to knowledge of processes and authority to implement changes, team members in these successful QI teams had to be proficient in disseminating information on performance and changes to processes. Teams developed regular communication channels across levels of the hospital hierarchy, from front‐line staff to executive management:
Communication, communication, communication. Make sure you have a system set up where there's opportunity for back and forth between all the different levels. Set up the infrastructure from the beginning where there's a mechanism to relay information up and down. Hospital #1, Cardiology Nurse
Discussion
We identified 5 behaviors of successful interdisciplinary QI teams based on our analysis of hospitals that reduced door‐to‐balloon times for patients with STEMI. These QI teams: (1) motivated involved hospital staff to consider lowering door‐to‐balloon times, a shared goal, (2) created opportunities for learning and problem‐solving, (3) addressed the impact of changes to care processes for patients with STEMI on staff, (4) protected the integrity of new care processes, and (5) represented each clinical discipline effectively by having members with in‐depth knowledge and authority.
Experts suggest that the key elements of effective teamwork in healthcare include prioritizing team over individual goals, mutual understanding, leadership, adaptability, and anticipation of the needs of others.26 These elements are supported by mutual trust and closed‐loop communication. The behaviors of QI teams in our study represent adaptive responses to the unique demands of QI in a complex organization. These teams went beyond an improvement model of identifying and analyzing a problem, and then developing and testing solutions by: (1) motivating and gathering information from each discipline, regardless of interdisciplinary conflicts; (2) responding to the concerns of front‐line staff, while maintaining control over the improvement process; and (3) sharing information across the hospital hierarchy. Table 3 illustrates potential relationships between the team behaviors in our data, the demands on hospital QI teams, and known elements of effective teamwork.
Demands on Hospital QI TeamsWhat QI Teams Must Do to Improve Care | Elements of Teamwork* | Behaviors of QI Teams in Our Study | Examples |
---|---|---|---|
| |||
Gather information from and motivate each involved discipline | Team rather than individual goals | Motivating all involved hospital staff towards a shared goal | Promote parity among disciplines |
Invite every involved discipline | |||
Emphasize benefit to patients | |||
Gather information from and motivate each involved discipline | Mutual understanding | Creating opportunities for learning | Allow for interdisciplinary disagreements |
Gather detailed operational knowledge in a mutual‐trust environment | |||
Guide changes using objective data | |||
Respond to the concerns of front‐line staff while maintaining control over the improvement process | Anticipate the needs of others | Addressing the impact of changes on staff | Validate concerns from all disciplines |
Test solutions to negative consequences (eg, call schedules, laboratory forms) | |||
Respond to the concerns of front‐line staff while maintaining control over the improvement process | Adaptability | Protecting the integrity of new protocols | Monitor data and respond to performance losses |
Document and publicize successes | |||
Empower front‐line staff to respond to lapses in protocol | |||
Keep all levels of the hospital hierarchy informed during he improvement process | Leadership | Representing each involved clinical discipline effectively | Select members with in‐depth knowledge about processes |
Select members with authority to implement changes within their discipline | |||
Exchange information with executive management and front‐line staff |
The behaviors in our study suggest effective teamwork strategies for QI. For example, our data suggest that successful interdisciplinary QI teams need effective representation from each involved discipline. This representation is necessary for motivation of front‐line staff, gathering of detailed information about processes, and the effective implementation of changes. Although this level of representation might challenge the cohesiveness of some teams,27 the teams in our sample managed conflict among disciplines without sacrificing the shared goal. By allocating attention and resources to the concerns of each discipline, the teams we studied prioritized team over individual goals and promoted mutual understanding.
Similarly, deciding when to modify the new protocols required leadership, adaptability, and anticipation of the needs of others. Successful QI teams in our sample modified protocols based on data and feedback, and created the mutual trust environment that is known to facilitate learning among disciplines.2830 Their willingness to learn, however, did not deter teams from protecting the integrity of new protocols. Lastly, participants stressed the importance of managing information across hierarchical boundaries. Managing reliable, timely, and accurate information across all levels is crucial to teamwork, and to the power and influence of a team.31
Our conclusions should be interpreted in light of several limitations. First, our study did not include a comparison group of low‐performing hospitals. We followed the recommendations of qualitative research experts23 who recommend sampling those with the most information on, and experience with, the phenomena under study (QI teams in high‐performing hospitals). The hypotheses we present here require further testing in quantitative studies of hospitals with diversity in QI team outcomes. Second, it is possible that sampled participants favored responses that they considered more desirable. To minimize this bias, we interviewed multiple participants per hospital, assured their confidentiality, and asked them to elaborate their responses. We sampled participants with a wide range of clinical and operational roles in each hospital, and also used the snowball sampling method to augment our sample. The range of responses collected, including frank discussions about setbacks, argues against the existence of contrasting behaviors to those captured. Third, although our sample included hospitals of various size and location, our findings might not reflect those of a larger sample of US hospitals. Last, the behaviors of QI teams may differ for other clinical processes.
Translating these findings into practice will require future studies of the impact of QI team behaviors on sustainability of quality gains. Since QI teams are not typically permanent, additional research is needed to identify behaviors associated with sustainable improvements. In addition, we must test whether the relationship between behaviors and team outcomes depends on whether the QI team strives to reach an evidence‐based goal or to improve a process as much as possible. Our sample demonstrated a combined approach, where the evidence‐based goal was followed by a desire to continue to further reduce door‐to‐balloon times. Similarly, the relationship between behaviors and team outcomes might depend on the catalyst for improvement (eg, regulatory pressure, an adverse event). The confluence of strong evidence and regulatory pressure that fueled these teams might not be true for other measures. Lastly, studies of teamwork in QI teams will require objective measures of team behaviors. A combination of surveys and direct team observation will likely be required to measure these behaviors, especially effective representation.
Our study highlights behaviors common to successful interdisciplinary QI teams in high‐performing hospitals. Previous studies have identified elements of teamwork and the importance of teams to QI, but have not examined team behaviors. In the era of an ever‐growing list of quality measures and of movement toward performance‐based reimbursement models,3234 hospitals have embraced the use of interdisciplinary teams as a key component of QI efforts. Our findings suggest that hospitals could enhance QI team effectiveness by promoting behaviors associated with successful interdisciplinary teams. When applied to QI teams, teamwork training could be supplemented with knowledge, attitudes, and skills regarding information‐gathering, problem‐solving, and communication across disciplines and levels of the hospital hierarchy.
Acknowledgements
The authors thank Harlan Krumholz for his mentorship; Tashonna Webster, Emily Cherlin, and Jeph Herrin for technical support; also the RWJ Clinical Scholars Program, Montefiore's DGIM faculty, and the participants of this study.
Interest in healthcare teams has surged in recent years. A majority of the interest has been devoted to teamwork in the interdisciplinary clinical teams that staff operating rooms,1 emergency departments,2 and other inpatient settings.3 Interventions that enhance elements of teamwork like communication, mutual support among team members, and leadership have demonstrated effectiveness.4
Less attention has been paid to improving the success of hospital quality improvement (QI) teams, which gather individuals from different disciplines to improve a defined aspect of care. Studies suggest that QI teams can enable transformational change in healthcare systems,57 and that interdisciplinary representation,8, 9 physician involvement,10, 11 and clear goals12, 13 are associated with successful QI efforts. However, few studies have examined the behaviors of the QI teams that planned and implemented these efforts. Understanding how QI teams work to achieve their goals will allow hospitals to encourage these behaviors, and allow researchers to design interventions to augment these behaviors.
Accordingly, we sought to characterize the behaviors of successful interdisciplinary hospital QI teams. We previously reported on the strategies used by hospitals to reduce door‐to‐balloon times for patients with ST‐elevation myocardial infarction (STEMI)14, 15 to the evidence‐based guideline of 90 minutes.16 Our objective is to examine how QI teams designed and implemented these strategies. We believe that studying high‐performing QI teams is a first step to developing testable hypotheses about the effectiveness of QI team behaviors and mechanisms by which these behaviors might produce positive team outcomes.
METHODS
We designed a qualitative study using in‐depth interviews. We selected a qualitative methodology, since behaviors, social norms, and interpersonal interactions can be most appropriately examined using qualitative methods.17, 18 In addition, we used a positive deviance approach,19 where we focused on hospitals with top performance and the most improvement in door‐to‐balloon times. We sampled from hospitals in the National Registry of Myocardial Infarction (NRMI) who perform percutaneous coronary intervention (PCI, n = 151). We selected hospitals whose median door‐to‐balloon times were 90 minutes (n = 35). Then, we ranked hospitals in descending order according to their improvement during the previous 3 years (19992002). We sampled hospitals in descending order until we reached theoretical saturation where, as recommended for qualitative inquiry,2022 additional site visits did not uncover new concepts or patterns regarding our study questions. All sampled hospitals agreed to participate.
The first contact at each hospital was typically the director of QI. We asked to interview anyone with substantial involvement in the effort to reduce door‐to‐balloon times, and suggested that a wide variety of disciplines and roles be represented. We also used the snowball technique,22 where we asked participants to provide the names of individuals with substantial involvement in the reducing door‐to‐balloon times. Participants had varied levels of participation in QI teams. We purposely asked for minority and dissenting views from all participants.
At least 2 members of the research team conducted in‐depth interviews during hospital site visits. Interviews were conducted individually or in small groups, and lasted 1 to 1.5 hours. All data were audiotaped after verbal consent. Our interviews began with the grand tour question: What, if anything, has this hospital done to reduce its door‐to‐balloon times for patients with STEMI? The research team used standardized probes20, 23 to guide the discussion and achieve a complete understanding of the phenomena under study, including leadership and activities of the QI teams, and recommendations to other hospitals that wished to reduce door‐to‐balloon times. As recommended by experts,23 our interview guide was purposefully open‐ended to capture the range of experiences with QI teams. We did not specifically probe for facilitating or challenging behaviors. Audiotapes were transcribed by an independent, professional transcriptionist.
For this analysis, we defined QI teams as groups of administrators, providers, and staff who designed, implemented, and monitored processes to reduce door‐to‐balloon times. Each analysis team member independently cataloged quotes about team behaviors using a list of concepts (or codes). We then analyzed the quotes to identify recurrent themes relevant to the behaviors of interdisciplinary QI teams. We used the constant comparative method of analysis,20, 24, 25 which stipulates that the initial list of codes is refined as new transcripts are analyzed, and the final list is applied to all the transcripts. The analysis team included experts in QI, medicine, qualitative and health services research, as well as organizational psychology, and one of the interviewers. The presence of diverse perspectives in the analysis team,21 and a detailed audit trail20 to document the emergence of codes and themes, helped enhance researcher neutrality, data accuracy, and validity. We used Atlas.ti version 5.2 (Scientific Software Development GMbH, Berlin, Germany) to assist in the analysis.
RESULTS
Our sample (n = 11) included hospitals that varied on several characteristics (eg, geographic location), and median door‐to‐balloon times ranged from 55.5 to 89.5 minutes (Table 1). Hospitals in our sample had higher mean improvements in door‐to‐balloon times compared with non‐sampled NRMI hospitals (n = 140, 24 minutes vs 3 minutes over 3 years). Our interview participants (n = 122) included physicians, nurses, QI personnel, and administrative staff (Table 2). Five behaviors emerged from the data analysis. We found that interdisciplinary QI teams in successful hospitals focused on: (1) motivating involved hospital staff towards a shared goal, (2) creating opportunities for learning and problem‐solving, (3) addressing the impact of changes in care processes on staff, (4) protecting the integrity of the newly developed care processes, and (5) representing each involved clinical discipline effectively. These behaviors were recurrent across our diverse set of hospitals.
Hospital | Region | Teaching Status | No. of Beds | STEMI Annualized Volume* | Median Door‐to‐Balloon Time (min) |
---|---|---|---|---|---|
| |||||
1 | Northeast | Yes | 770 | 68 | 85.5 |
2 | Midwest | Yes | 176 | 33 | 75.5 |
3 | South | Yes | 870 | 187 | 55.5 |
4 | Midwest | Yes | 426 | 85 | 70.5 |
5 | South | No | 350 | 94 | 69.0 |
6 | West | Yes | 204 | 89 | 82.0 |
7 | West | Yes | 277 | 41 | 89.0 |
8 | South | Yes | 633 | 124 | 86.5 |
9 | West | No | 190 | 43 | 89.5 |
10 | West | No | 111 | 51 | 87.0 |
11 | Midwest | Yes | 276 | 95 | 87.0 |
Participants | No. in Sample (n = 122) |
---|---|
| |
Cardiology | |
MD | 20 |
Nurse | 15 |
Emergency Medicine | |
MD | 15 |
Nurse | 9 |
EMS | 3 |
Executive managers | 20 |
QI personnel | 17 |
Other nurses | 13 |
Other clinical/support staff | 10 |
Motivating Involved Hospital Staff Toward a Shared Goal
As with any team, the QI teams in our sample had to motivate others in order to be successful:
Making certain that we have common goals [and] figuring out the best way to get there. It has to be a team, a partnership. It can't be I'm better than you, or this discipline is better than that discipline. We're all here for one reason. Hospital #11, Administrator
To redesign the door‐to‐balloon care process, successful QI teams engaged clinical disciplines that felt disempowered previously:
[ED physicians] were receptive, but they said, Cardiology won't let us do this. It's not going to be [just] cardiology anymore; it has to be everybody, because we really need to improve this time. Hospital #7, QI personnel
Teams also promoted reduction in door‐to‐balloon times as a goal that required shared participation from clinical disciplines including cardiology and emergency medicine, but also laboratory medicine, critical care, pharmacy, and transport. Achieving this goal would positively impact institutional standing:
When people get entrenched in their little domes they have a hard time seeing the overall benefit. Stress the institutional importance of this issue and the importance of cooperation and how it translates to better patient outcomes. [This is what] we're being monitored on; a very clear way in which we can be judged. Hospital #7, Catheterization Lab Medical Director
Creating Opportunities for Learning and Problem‐Solving
The work of these QI teams resulted in interdisciplinary conflict, but when individuals voiced frustration with other disciplines, it was seen as a necessary step in the redesign of a complex, interdisciplinary care process:
The first 6 to 8 months were spent team building and dealing with the vying for control. It was a total waste of time but necessary because now it was an interdisciplinary thing. It wasn't something we were trying to change within one service. We were asking everyone to sit down and agree about what they were going to do. The first [meetings] were shouting matches. The ED was becoming a scapegoat; the problem was never in the cath lab. We were able to act on some of those issues. You need to see both sides and understand what the barriers are. Hospital #1, Cardiology Nurse
Although challenging, interdisciplinary QI teams allowed team members to gain the detailed knowledge about front‐line operations that they needed:
We cardiologists don't really deal with what is happening behind the scenesexactly what a unit clerk does, and where the bottlenecks are. I discovered that lots of ideas come from unexpected places. Hospital #11, Cardiologist
To facilitate learning, teams cultivated a nonjudgmental, mutual trust atmosphere:
Throughout the whole process, there's been a lot of dialogue. Everybody throws their assumptions on the table, assumptions are respected; there is a lot of open communication. Hospital #3, Cardiology QI personnel
In addition, reducing door‐to‐balloon times required iterative problem‐solving. QI teams in our sample welcomed opportunities to learn from less effective strategies:
I'm one that's never too upset to ditch something if something was working and you switched to something else and now it's not working. You tried it. Go back. Or maybe it needs to be fine tuned. Hospital #1, Administrator
Addressing the Impact of Changes in Care Processes on Staff
Many hospitals in our sample required staff to arrive at the catheterization lab within 2030 minutes of being paged. This resulted in more demanding call schedules and changing roles (eg, activation of the cath lab by emergency department [ED] physicians instead of cardiologists). Participants conveyed both the burden of, and the satisfaction with, new processes:
It is a tremendous commitment time‐wise. We had a first call schedule but had to go to a second call schedule. There's no way you can get around the fact that it's very disruptive to your life. You're sitting down to dinner and suddenly you've got to go, and you don't have a chance to kiss the kids goodbye. You're out the door and heading to the hospital. It's been very disruptive, but it's a good program. No one regrets it. Hospital #5, Cardiologist
Successful QI teams validated staff concerns about the impact of these changes on workflow and quality of life:
We have few people who are nay saying for the sake of nay saying. People have legitimate concerns. I value those concerns as they affect the people who are involved. Hospital #4, Cardiologist
Teams responded to these concerns by testing solutions and eliminating negative consequences where possible:
[ED said]: We're uncomfortable with being the ordering physicians for labs drawn after patients leave the ED. I said, Let's make that issue go away. If they perceive it as a risk, let's make that fear go away because that removes a barrier. Hospital #4, Cardiologist
Protecting the Integrity of the New Care Processes
Once the necessary changes to the care of patients with STEMI were in place, these teams ensured that new processes were followed consistently. Rather than allowing customization of the processes by front‐line staff, QI teams monitored cases, gathered feedback, and made necessary modifications. Small modifications to the protocols helped incorporate front‐line feedback and reinvigorate staff:
People got comfortable and slower, and I quit hassling the group. We reinvigorated the Emergency Room, met with them, and changed the process a little bit. Change always perks people's attention. Hospital #8, Cardiologist
Another strategy to protect the integrity of the redesigned process was to highlight its value by publicizing clinical successes:
[We] let them know what we found and how the patient is doing. It's a pat on the back saying you did a good job. Next time [the ED physicians] will be screening that much closer. When we're leaving the hospital at 3 a.m. they'll say How did it go? They want to know; that adds to that team feeling because everybody is important. They help us do our job and we help them do theirs. Hospital #9, Catheterization Lab Technologist
Lastly, QI teams empowered front‐line staff to comply with the new process by emphasizing benefit to patients. This allowed staff to overcome hierarchical boundaries:
ED staff told us that sometimes patients waited because the cardiologist was getting a history and physical. They've been empowered to say We're ready to go. Before nurses felt that they couldn't really do that. Now we're getting through to them that time is muscle and that guy is costing the patient. Hospital #5, QI personnel
Representing Each Involved Clinical Discipline Effectively
Participants remarked on the importance of team member selection. Successful QI teams had members who could effectively represent each involved discipline. Effective representation involved in‐depth knowledge of one's aspect of the care process and communicating that perspective to the team:
The lab director got together with the ED director, who got together with the radiology director, who asked Who's transporting the patient?; How are we going to get blood drawn, what's going to happen? That middle management team became critical. Hospital #10, Administrator
Effective representation also required the authority to endorse and implement necessary changes:
The people that head councils are not people in the position to make changes in the workflow of the hospital. For example, having the ED doctor activate the cath lab. You'd say Well, the Chairman of Medicine would probably have something to do with this. Wrong. The Chairman of Medicine has no interest in STEMI care. Go to the Chairman of Cardiology. Sounds good, but you have to talk to the interventional guys. Go to the head of the cath lab. Sounds good, but it really has to go to a cath lab committee meeting. Hospital #1, QI personnel
In addition to knowledge of processes and authority to implement changes, team members in these successful QI teams had to be proficient in disseminating information on performance and changes to processes. Teams developed regular communication channels across levels of the hospital hierarchy, from front‐line staff to executive management:
Communication, communication, communication. Make sure you have a system set up where there's opportunity for back and forth between all the different levels. Set up the infrastructure from the beginning where there's a mechanism to relay information up and down. Hospital #1, Cardiology Nurse
Discussion
We identified 5 behaviors of successful interdisciplinary QI teams based on our analysis of hospitals that reduced door‐to‐balloon times for patients with STEMI. These QI teams: (1) motivated involved hospital staff to consider lowering door‐to‐balloon times, a shared goal, (2) created opportunities for learning and problem‐solving, (3) addressed the impact of changes to care processes for patients with STEMI on staff, (4) protected the integrity of new care processes, and (5) represented each clinical discipline effectively by having members with in‐depth knowledge and authority.
Experts suggest that the key elements of effective teamwork in healthcare include prioritizing team over individual goals, mutual understanding, leadership, adaptability, and anticipation of the needs of others.26 These elements are supported by mutual trust and closed‐loop communication. The behaviors of QI teams in our study represent adaptive responses to the unique demands of QI in a complex organization. These teams went beyond an improvement model of identifying and analyzing a problem, and then developing and testing solutions by: (1) motivating and gathering information from each discipline, regardless of interdisciplinary conflicts; (2) responding to the concerns of front‐line staff, while maintaining control over the improvement process; and (3) sharing information across the hospital hierarchy. Table 3 illustrates potential relationships between the team behaviors in our data, the demands on hospital QI teams, and known elements of effective teamwork.
Demands on Hospital QI TeamsWhat QI Teams Must Do to Improve Care | Elements of Teamwork* | Behaviors of QI Teams in Our Study | Examples |
---|---|---|---|
| |||
Gather information from and motivate each involved discipline | Team rather than individual goals | Motivating all involved hospital staff towards a shared goal | Promote parity among disciplines |
Invite every involved discipline | |||
Emphasize benefit to patients | |||
Gather information from and motivate each involved discipline | Mutual understanding | Creating opportunities for learning | Allow for interdisciplinary disagreements |
Gather detailed operational knowledge in a mutual‐trust environment | |||
Guide changes using objective data | |||
Respond to the concerns of front‐line staff while maintaining control over the improvement process | Anticipate the needs of others | Addressing the impact of changes on staff | Validate concerns from all disciplines |
Test solutions to negative consequences (eg, call schedules, laboratory forms) | |||
Respond to the concerns of front‐line staff while maintaining control over the improvement process | Adaptability | Protecting the integrity of new protocols | Monitor data and respond to performance losses |
Document and publicize successes | |||
Empower front‐line staff to respond to lapses in protocol | |||
Keep all levels of the hospital hierarchy informed during he improvement process | Leadership | Representing each involved clinical discipline effectively | Select members with in‐depth knowledge about processes |
Select members with authority to implement changes within their discipline | |||
Exchange information with executive management and front‐line staff |
The behaviors in our study suggest effective teamwork strategies for QI. For example, our data suggest that successful interdisciplinary QI teams need effective representation from each involved discipline. This representation is necessary for motivation of front‐line staff, gathering of detailed information about processes, and the effective implementation of changes. Although this level of representation might challenge the cohesiveness of some teams,27 the teams in our sample managed conflict among disciplines without sacrificing the shared goal. By allocating attention and resources to the concerns of each discipline, the teams we studied prioritized team over individual goals and promoted mutual understanding.
Similarly, deciding when to modify the new protocols required leadership, adaptability, and anticipation of the needs of others. Successful QI teams in our sample modified protocols based on data and feedback, and created the mutual trust environment that is known to facilitate learning among disciplines.2830 Their willingness to learn, however, did not deter teams from protecting the integrity of new protocols. Lastly, participants stressed the importance of managing information across hierarchical boundaries. Managing reliable, timely, and accurate information across all levels is crucial to teamwork, and to the power and influence of a team.31
Our conclusions should be interpreted in light of several limitations. First, our study did not include a comparison group of low‐performing hospitals. We followed the recommendations of qualitative research experts23 who recommend sampling those with the most information on, and experience with, the phenomena under study (QI teams in high‐performing hospitals). The hypotheses we present here require further testing in quantitative studies of hospitals with diversity in QI team outcomes. Second, it is possible that sampled participants favored responses that they considered more desirable. To minimize this bias, we interviewed multiple participants per hospital, assured their confidentiality, and asked them to elaborate their responses. We sampled participants with a wide range of clinical and operational roles in each hospital, and also used the snowball sampling method to augment our sample. The range of responses collected, including frank discussions about setbacks, argues against the existence of contrasting behaviors to those captured. Third, although our sample included hospitals of various size and location, our findings might not reflect those of a larger sample of US hospitals. Last, the behaviors of QI teams may differ for other clinical processes.
Translating these findings into practice will require future studies of the impact of QI team behaviors on sustainability of quality gains. Since QI teams are not typically permanent, additional research is needed to identify behaviors associated with sustainable improvements. In addition, we must test whether the relationship between behaviors and team outcomes depends on whether the QI team strives to reach an evidence‐based goal or to improve a process as much as possible. Our sample demonstrated a combined approach, where the evidence‐based goal was followed by a desire to continue to further reduce door‐to‐balloon times. Similarly, the relationship between behaviors and team outcomes might depend on the catalyst for improvement (eg, regulatory pressure, an adverse event). The confluence of strong evidence and regulatory pressure that fueled these teams might not be true for other measures. Lastly, studies of teamwork in QI teams will require objective measures of team behaviors. A combination of surveys and direct team observation will likely be required to measure these behaviors, especially effective representation.
Our study highlights behaviors common to successful interdisciplinary QI teams in high‐performing hospitals. Previous studies have identified elements of teamwork and the importance of teams to QI, but have not examined team behaviors. In the era of an ever‐growing list of quality measures and of movement toward performance‐based reimbursement models,3234 hospitals have embraced the use of interdisciplinary teams as a key component of QI efforts. Our findings suggest that hospitals could enhance QI team effectiveness by promoting behaviors associated with successful interdisciplinary teams. When applied to QI teams, teamwork training could be supplemented with knowledge, attitudes, and skills regarding information‐gathering, problem‐solving, and communication across disciplines and levels of the hospital hierarchy.
Acknowledgements
The authors thank Harlan Krumholz for his mentorship; Tashonna Webster, Emily Cherlin, and Jeph Herrin for technical support; also the RWJ Clinical Scholars Program, Montefiore's DGIM faculty, and the participants of this study.
- The efficacy of medical team training: improved team performance and decreased operating room delays.Ann Surg.2010;252:477–485. , , .
- Error reduction and performance improvement in the Emergency Department through formal teamwork training: evaluation results of the MedTeams project.Health Serv Res.2002;37:1553–1581. , , , et al.
- Interventions to improve team effectiveness: a systematic review.Health Policy.2010;94:183–195. , , , .
- The anatomy of health care team training and the state of practice: a critical review.Acad Med. doi: 10.1097/ACM.0b013e3181f2e907 [published Online First: Sep 21, 2010]. , , , et al.
- Microsystems in health care: part 1. Learning from high‐performing front‐line clinical units.Jt Comm J Qual Saf.2002;28:472–493. , , , et al.
- Organizational factors associated with high performance in quality and safety in academic medical centers.Acad Med.2007;82:1178–1186. , , , , , .
- Transformational change in health care systems: an organizational model.Health Care Manage Rev.2007;32:309–320. , , , et al.
- Treatment teams that work (and those that don't): an application of Hackman's group effectiveness model to interdisciplinary teams in psychiatric hospitals.J Appl Behav Sci.1995;31:303–327. .
- What do we know about health care team effectiveness? A review of the literature.Med Care Res Rev.2006;63:263–300. , .
- Understanding team‐based quality improvement for depression in primary care.Health Serv Res.2002;37:1009–1029. , , , et al.
- The role of perceived team effectiveness in improving chronic illness care.Med Care.2004;42:1040–1048. , , , et al.
- The determinants of effectiveness in primary health care teams.J Interprof Care.1999;13:7–18. , .
- Characteristics of successful quality improvement teams: lessons from five collaborative projects in the VHA.Jt Comm J Qual Saf.2004;30:152–162. , .
- Achieving door‐to‐balloon times that meet quality guidelines: how do successful hospitals do it?J Am Coll Cardiol.2005;46:1236–1241. , , , et al.
- Achieving rapid door‐to‐balloon times: how top hospitals improve complex clinical systems.Circulation.2006;113:1079–1085. , , , et al.
- ACC/AHA guidelines for the management of patients with ST‐elevation myocardial infarction: a report of the ACC/AHA Task Force on Practice Guidelines (Committee to Revise the 1999 Guidelines on the Management of Patients with Acute Myocardial Infarction).Circulation.2004;110:e82–e293. , , , et al.
- Reaching the parts other methods cannot reach: an introduction to qualitative methods in health and health services research.BMJ.1995;311:42–45. , .
- Qualitative and mixed methods provide unique contributions to outcomes research.Circulation.2009;119:1442–1452. , , .
- Research in action: using positive deviance to improve quality of health care.Implement Sci.2009;4:25. doi: 10.1186/1748–5908‐4–25 [published Online First: May 8, 2009]. , , , , , .
- Miles MB, Huberman AM, eds.Qualitative Data Analysis: An Expanded Sourcebook.Thousand Oaks, CA:Sage,1994.
- Crabtree BF, Miller WL, eds.Doing Qualitative Research.London:Sage,1999.
- Qualitative research in health care: assessing quality in qualitative research.BMJ.2000;320:50–52. , .
- Qualitative Research 42:1758–1772. .
- Discovery of Grounded Theory.Chicago, IL:Aldine,1967. , .
- Does team training work? Principles for health care.Acad Emerg Med.2008;15:1002–1009. , , , .
- Senior executive teams: not what you think.Consult Psychol J Pract Res.2005;57:107–117. .
- Psychological safety and learning behavior in work teams.Admin Sci Q.1999;44:350–383. .
- Making it safe: the effects of leader inclusiveness and professional status on psychological safety and improvement efforts in health care teams.J Organiz Behav.2006;27:941–966. , .
- Learning from preventable adverse events in health care organizations: development of a multilevel model of learning and propositions.Health Care Manage Rev.2007;32:330–340. , , .
- Managing with Power: Politics and Influence in Organizations.Boston, MA:Harvard Business School Press,1993:111–125. .
- Using Medicare payment policy to transform the health system: a framework for improving performance.Health Aff.2009;28:w238–w250. , , , .
- Value‐driven health care: implications for hospitals and hospitalists.J Hosp Med.2009;4:507–511. .
- Medicare program: hospital inpatient value‐based purchasing program, proposed rule.Fed Reg.76(9):2454–2491.
- The efficacy of medical team training: improved team performance and decreased operating room delays.Ann Surg.2010;252:477–485. , , .
- Error reduction and performance improvement in the Emergency Department through formal teamwork training: evaluation results of the MedTeams project.Health Serv Res.2002;37:1553–1581. , , , et al.
- Interventions to improve team effectiveness: a systematic review.Health Policy.2010;94:183–195. , , , .
- The anatomy of health care team training and the state of practice: a critical review.Acad Med. doi: 10.1097/ACM.0b013e3181f2e907 [published Online First: Sep 21, 2010]. , , , et al.
- Microsystems in health care: part 1. Learning from high‐performing front‐line clinical units.Jt Comm J Qual Saf.2002;28:472–493. , , , et al.
- Organizational factors associated with high performance in quality and safety in academic medical centers.Acad Med.2007;82:1178–1186. , , , , , .
- Transformational change in health care systems: an organizational model.Health Care Manage Rev.2007;32:309–320. , , , et al.
- Treatment teams that work (and those that don't): an application of Hackman's group effectiveness model to interdisciplinary teams in psychiatric hospitals.J Appl Behav Sci.1995;31:303–327. .
- What do we know about health care team effectiveness? A review of the literature.Med Care Res Rev.2006;63:263–300. , .
- Understanding team‐based quality improvement for depression in primary care.Health Serv Res.2002;37:1009–1029. , , , et al.
- The role of perceived team effectiveness in improving chronic illness care.Med Care.2004;42:1040–1048. , , , et al.
- The determinants of effectiveness in primary health care teams.J Interprof Care.1999;13:7–18. , .
- Characteristics of successful quality improvement teams: lessons from five collaborative projects in the VHA.Jt Comm J Qual Saf.2004;30:152–162. , .
- Achieving door‐to‐balloon times that meet quality guidelines: how do successful hospitals do it?J Am Coll Cardiol.2005;46:1236–1241. , , , et al.
- Achieving rapid door‐to‐balloon times: how top hospitals improve complex clinical systems.Circulation.2006;113:1079–1085. , , , et al.
- ACC/AHA guidelines for the management of patients with ST‐elevation myocardial infarction: a report of the ACC/AHA Task Force on Practice Guidelines (Committee to Revise the 1999 Guidelines on the Management of Patients with Acute Myocardial Infarction).Circulation.2004;110:e82–e293. , , , et al.
- Reaching the parts other methods cannot reach: an introduction to qualitative methods in health and health services research.BMJ.1995;311:42–45. , .
- Qualitative and mixed methods provide unique contributions to outcomes research.Circulation.2009;119:1442–1452. , , .
- Research in action: using positive deviance to improve quality of health care.Implement Sci.2009;4:25. doi: 10.1186/1748–5908‐4–25 [published Online First: May 8, 2009]. , , , , , .
- Miles MB, Huberman AM, eds.Qualitative Data Analysis: An Expanded Sourcebook.Thousand Oaks, CA:Sage,1994.
- Crabtree BF, Miller WL, eds.Doing Qualitative Research.London:Sage,1999.
- Qualitative research in health care: assessing quality in qualitative research.BMJ.2000;320:50–52. , .
- Qualitative Research 42:1758–1772. .
- Discovery of Grounded Theory.Chicago, IL:Aldine,1967. , .
- Does team training work? Principles for health care.Acad Emerg Med.2008;15:1002–1009. , , , .
- Senior executive teams: not what you think.Consult Psychol J Pract Res.2005;57:107–117. .
- Psychological safety and learning behavior in work teams.Admin Sci Q.1999;44:350–383. .
- Making it safe: the effects of leader inclusiveness and professional status on psychological safety and improvement efforts in health care teams.J Organiz Behav.2006;27:941–966. , .
- Learning from preventable adverse events in health care organizations: development of a multilevel model of learning and propositions.Health Care Manage Rev.2007;32:330–340. , , .
- Managing with Power: Politics and Influence in Organizations.Boston, MA:Harvard Business School Press,1993:111–125. .
- Using Medicare payment policy to transform the health system: a framework for improving performance.Health Aff.2009;28:w238–w250. , , , .
- Value‐driven health care: implications for hospitals and hospitalists.J Hosp Med.2009;4:507–511. .
- Medicare program: hospital inpatient value‐based purchasing program, proposed rule.Fed Reg.76(9):2454–2491.
Copyright © 2011 Society of Hospital Medicine