The comprehensive care project: measuring physician performance in ambulatory practice.

OBJECTIVE: To investigate the feasibility, reliability, and validity of comprehensively assessing physician-level performance in ambulatory practice. DATA SOURCES/STUDY SETTING: Ambulatory-based general internists in 13 states participated in the assessment. STUDY DESIGN: We assessed physician-level performance, adjusted for patient factors, on 46 individual measures, an overall composite measure, and composite measures for chronic, acute, and preventive care. Between- versus within-physician variation was quantified by intraclass correlation coefficients (ICC). External validity was assessed by correlating performance on a certification exam. DATA COLLECTION/EXTRACTION METHODS: Medical records for 236 physicians were audited for seven chronic and four acute care conditions, and six age- and gender-appropriate preventive services. PRINCIPAL FINDINGS: Performance on the individual and composite measures varied substantially within (range 5-86 percent compliance on 46 measures) and between physicians (ICC range 0.12-0.88). Reliabilities for the composite measures were robust: 0.88 for chronic care and 0.87 for preventive services. Higher certification exam scores were associated with better performance on the overall (r = 0.19; p