THE PRIMARY-CARE ASSESSMENT SURREY - TESTS OF DATA QUALITY AND MEASUREMENT PERFORMANCE

OBJECTIVES. The authors examine the data quality and measurement perfo rmance of the Primary Care Assessment Survey (PCAS), a patient-complet ed questionnaire that operationalizes formal definitions of primary ca re, including the definition recently proposed by the Institute of Med icine Committee on the Future of Primary Care. METHODS. The PCAS measu res seven domains of care through 11 summary scales: accessibility (or ganizational, financial), continuity (longitudinal, visit-based), comp rehensiveness (contextual knowledge of patient, preventive counseling) , integration, clinical interaction (clinician-patient communication, thoroughness of physical examinations), interpersonal treatment, and t rust. Data from a study of Massachusetts state employees (n = 6094) we re used to evaluate key measurement properties of the 11 PCAS scales. Analyses were performed on the combined population and for each of the 16 subgroups defined according to sociodemographic and health charact eristics. RESULTS. The 11 PCAS scales demonstrated consistently strong measurement characteristics across all subgroups of this adult popula tion. Tests of scaling assumptions for summated rating scales were wel l satisfied by all Likert;scaled measures. Assessment of data complete ness, scale score dispersion characteristics, and inter-scale correlat ions provide strong evidence for the soundness of all scales, and for the value of separately measuring and interpreting these concepts. CON CLUSIONS. With public and private sector policies increasingly emphasi zing the importance of primary care, the need for tools to evaluate an d improve primary care performance is clear. The PCAS has excellent me asurement properties, and performs consistently well across varied seg ments of the adult population. Widespread application of an assessment methodology, such as the PCAS, will afford an empiric basis through w hich to measusre, monitor, and continuously improve primary care.