Objectives: The authors estimate separately contributions of each component intervention to overall effectiveness of quality assurance cycles used to improve practice performance.
Methods: In a randomized, controlled trial, experimental cycles of quality assurance were conducted for eight patient-care guidelines, with two experimental cycles assigned to each of 16 group practices. For three separate interventions per cycle, practitioners: (1) were notified of the name of the experimental guideline, (2) discussed criteria of conformance to the guideline, and (3) received feedback on performance. Actions taken in response to interventions were documented. Using medical records data for a baseline year and for 3 months after each intervention and an additional 9 months, the authors scored each practice for conformance to two experimental guidelines and to control guidelines.
Results: For all patient-care guidelines combined, and for four of five guidelines showing improvement, knowledge of guidelines and review criteria alone produced no change. After feedback, performance improved and improvement persisted for at least 9 months. The number of corrective actions implemented contributed significantly to effectiveness of quality assurance.
Conclusions: Feedback to providers of data on their performance is a more powerful stimulus for quality improvement than is knowledge of guidelines or discussion of review criteria.