Little data are available to assess the efforts of managed care organizations to improve quality of care. This analysis assessed differences in performance rates between organizations with and without quality improvement activities.

We reviewed 399 self-reported quality improvement activities submitted by organizations seeking accreditation by the National Committee for Quality Assurance. Processes or outcomes assessed in quality improvement activities were linked to corresponding measures in the effectiveness-of-care database of the Health Plan Employer Data and Information Set (HEDIS). Performance rates for managed care organizations with and without quality improvement activities were then compared.

The cross-sectional analysis included 79 quality improvement activities from 50 organizations, covering 12 effectiveness-of-care categories. Each activity had a matching performance score in the database. Financial incentives for providers were associated with substantially higher performance rates in organizations employing this type of intervention. Eight effectiveness-of-care categories had at least four organizations reporting specific quality improvement activities for the care category of interest; statistically significant improvements were observed for follow-up visits for patients after hospitalization for mental illness, checkups after delivery, and screening for cervical cancer.

Based on objective and audited information, the estimated effects of self-reported quality improvement activities were often small and inconsistent. In some instances, the observed effect was contrary to the expected direction. Limitations of the available dataset and the caveats of a cross-sectional study design precluded a number of analytical options. Longer-term, prospective studies are needed to explore further the relation between quality improvement activities and objective measures of clinical performance.