Review of studies that compare the quality of cardiovascular care in HMO versus non-HMO settings

OBJECTIVES: The authors compared the quality of cardiovascular care in health maintenance organizations (HMOs) versus traditional insurance arrangements through an analysis of existing literature. METHODS: Data were derived from all peer-reviewed studies published through November 1995 that used process or outcome measures to evaluate the quality of cardiovascular care in HMO versus non-HMO settings. A standardized form was used to extract information from each study on: condition studied, study time frame, type of study design, type of comparison groups, characteristics of patients and physicians, process and outcome measures used, data collection methods, reliability and validity of quality measurements, risk adjustment techniques, findings about quality of care, summary of other findings, study limitations, and other comments that explained the context of the research. RESULTS: Seven of the 11 studies that examined process measures for cardiovascular care in HMO versus non-HMO patients found more differences in one or more process measures that favored HMOs than non-HMOs. Seven of the 10 studies that examined outcome measures found no statistically significant differences in patient care between HMO and non-HMO settings. The other three studies presented contradictory results. CONCLUSIONS: The existing literature suggests that the outcomes of care for cardiovascular conditions do not differ between HMO and non-HMO settings, although selected measures of the process of cardiovascular care are actually better in HMO than in non-HMO settings.