METHODS: The study participants were randomly selected from patients in a health maintenance organization group and a low-income group in South Carolina. They were either surveyed or interviewed regarding the achievement of primary care. Reliability, validity, and scaling analyses were conducted to assess and validate the 9 scales representing core primary care subdomains and 3 derivative domains: first contact accessibility, first contactutilization (first contact domain), longitudinalityinterpersonal relationships (longitudinality domain), coordination of services (coordination domain), comprehensive-nessservices available, comprehensiveness services received (comprehensiveness domain), family centeredness, community orientation, and cultural competence (derivative domains).
RESULTS: The results indicate that the hypothesized scales for primary care have substantial reliability and validity, and the extracted factors explained 88.1% of the total variance in the item scores. All of the 5 scaling assumptions (item-convergent validity, item-discriminant validity, equal item variance, equal itemscale correlation, and score reliability) were met, suggesting that these items may be used to represent the primary care scales and the scoring of these items may be summed without standardization or weighting.
CONCLUSIONS: Psychometric assessment supported the integrity and general adequacy of the PCAT-AE for assessing the characteristics and quality of primary care for adults. The PCAT-AE can be used as a quality measurement tool that assesses the adequacy of primary care experience.
Agrowing body of literature at both individual and ecologic levels has demonstrated the association of primary care and health outcomes.1-11 Franks and Fiscella,12 using nationally representative survey data, showed that adult respondents who reported a primary care physician rather than a specialist as their regular source of care had lower subsequent mortality and lower annual health care costs after controlling for differences in demographic characteristics, health insurance status, health perceptions, reported diagnoses, and smoking status. Both Shi4,6 and Farmer and collegues13 found better health outcomes in states with higher primary care physician-population ratios after controlling for sociodemographic measures (% elderly, % urban, % minority, education, income, unemployment, pollution) and lifestyle factors (seatbelt usage, obesity, and smoking). Recent studies further showed that primary care may mitigate the adverse effects of income inequality on health.14-16 Taken individually, each of the main features of primary care (person-focused care over time, accessible care, comprehensive in the sense of meeting all common health needs, and coordination when people have to receive services elsewhere) are known to improve both the effectiveness as well as the efficiency of care.1,7,17-24
The mounting evidence associating primary care with improved health outcome has led to a rapid increase in interest in assessing primary care achievement by consumers and patients.18,19,21,25-28 Despite its importance, there currently is no way to assess the extent to which people receive adequate primary care; receiving care from a physician or physician designated as a primary care physician is at best only a proxy for actual adequacy of provision of primary care services. As a result, there are efforts to develop instruments that directly assess the adequacy of primary care.20,29,30
The Primary Care Assessment Tool (PCAT) instruments developed by The Johns Hopkins Primary Care Policy Center for Underserved Populations were designed to measure the extent and quality of primary care services at a provider setting designated by consumers as their main source of general care and consistent with a focus on attributes of primary care that have been demonstrated to produce better outcomes of care at lower costs.22 The PCATfamily of instruments includes the Child Consumer/Client Survey, the Adult Consumer/Client Survey, and the Facility/Provider Survey. All surveys are based on self-report by patients or providers. The Consumer/Client Survey (both adult and child editions) is designed to collect information from consumers or family caretakers regarding their experience using health care resources. It may be used to survey target populations as defined by geography (community surveys), health plans, sites of care, payment mechanisms, or specific health care needs. The survey, which takes approximately 40 minutes to complete, can be administered through either telephone or face-to-face interviews, or by mail. Ahigh school reading level is required to self-administer the questionnaire. The Facility/Provider Survey is designed to collect information about specific operational characteristics and practices related to providing primary care from the viewpoint of practitioners, clinics, group practices, and institutions. This survey can also be implemented either by mail or by face-to-face or telephone interviews. It is parallel in content to the consumer/client survey. All 3 instruments are available for general use on request.