Methods
Subjects, survey mailings, and response rates
A sampling frame, previously described,22,23 was constructed from the American Medical Association’s Physician Masterfile. The target population was the 171,252 civilian physicians listed as participating in direct patient care (rather than in training, administration, teaching, inactive, etc), including generalists (family physicians, general internists, and general pediatricians; general practitioners were not included) and specialists (medical and pediatric nonsurgical subspecialists) in the United States. We stratified the frame into geographic regions of high and low penetration of managed care, non-Hispanic white vs other physician ethnicity, and the 5-targeted specialty groupings.
We drew a random sample of 5704 physicians, oversampling smaller strata. Questionnaires and up to 3 follow-up mailings were sent to the sample from January through September 1997. A total of 2325 physicians responded, 52% when corrected for noncontact and ineligibility.24 Based on information on the Masterfile, response rates did not differ by age, for those in office vs hospital-based practices, or for those in communities of high vs low managed care penetration. However, response rates were higher for subspecialists than for generalists, US medical graduates than for international graduates, and those for whom race-ethnicity was listed as black, “missing,” or “other” than for those listed as Hispanic, non-Hispanic white, or Asian. Statistical weighting in analyses adjusted for group contact and response rate differences.
We dropped the 218 respondents who worked less than 25 hours per week in activities related to patient care and another 169 physicians who primarily practiced outside of their specialty, such as general internists who worked as endocrinologists or oncologists. Analyses were based on the remaining 1939 physicians.
Questionnaire design and analyses
The questionnaire included 36 declarative statements about physicians’ views and regard for various features of their work and practices, to which respondents provided Likert-scaled responses from “strongly agree” to “strongly disagree.”22 Representative statements were, “I feel a strong personal connection with my patients” and “My total compensation package is fair.” These items were drawn from previous studies of physician satisfaction, from issues raised in physician focus groups we assembled, and through the suggestions of experts. We then used exploratory factor analysis with a pilot physician sample, followed by confirmatory factor analysis with a validation physician sample to group these items into 10 scales reflecting physicians’ satisfaction with 10 aspects of their work.22,23 Scale alpha coefficients of reliability ranged from 0.65 to 0.77.
Physicians’ anticipated departure from their jobs was measured through a questionnaire item asking “What is the likelihood that you will leave your current practice situation within two years?”, with allowable responses of “none,” “slight,” “moderate,” “likely,” and “definitely.” Social psychology research has substantiated the use of people’s expressed intentions as measures of their future behavior.25 Prior studies26-28 have used anticipated departure and anticipated retention as expeditious proxy indicators for actual job departure and retention, with correlation coefficients between workers’ plans to leave and subsequent departure typically measured at about 0.5. In the only validating physician study, rural physicians in Western Australia much more often left their practices if they had predicted 10 years earlier that they would (odds ratio [OR], 3.3).29 Shorter-term predictions, such as the 2-year time horizon used in this study, should be even more accurate.
This study’s dichotomous outcome indicator-whether physicians anticipated leaving their jobs within 2 years-defined planned “leavers” as those who indicated a moderate, likely, or definite likelihood of leaving their practices; planned “retainees” were those who envisioned only a slight or no chance of leaving. This cut point was selected for both its face validity-falling at the scale point at which leaving became a real possibility for subjects and no longer an unlikely event-and because it yielded an adequately balanced split in outcome values.
In analyses, levels of satisfaction with the 10 aspects of work and anticipated job departure were described for generalists, specialists, and physicians in 3 age groups. We compared groups on satisfaction levels and anticipated departure rates with t tests and 1-way analysis of variance.
We used logistic regression analysis to model separately the anticipated departure of each of the 5 groups. We entered satisfaction levels for each of the 10 areas of work into the models as 2 dichotomous (dummy) variables, yielding 20 satisfaction indicator variables. Ten of these indicators reflected values in the top quartile of satisfaction (ie, top quartile vs lower 3 quartiles) in each area of work and another 10 indicators reflected values in the lowest quartile of satisfaction (bottom quartile vs upper 3 quartiles). Cut points for the middle vs high satisfaction groups for the 10 areas of work ranged from 3.0 to 4.25 on the satisfaction scale (in which 1 indicated dissatisfaction; 3, neutral; and 5, satisfaction); for the middle vs lower satisfaction group, cut points ranged from 2.0 to 3.33. The inclusion of dichotomous indicators of high and low satisfaction for each area of work treated the middle 2 satisfaction quartiles statistically as the omitted, comparison category. This analytic approach modeled the effects on anticipated departure of relatively high and low satisfaction levels for each area of work, compared with more typical, midrange satisfaction levels, simultaneously controlling for relative satisfaction in the other 9 areas of work. We also included control variables for sex, age, and whether physicians owned their practices.