Variation in Detection of Adenomas and Polyps by Colonoscopy and Change Over Time With a Performance Improvement Program

Background & Aims: There has been no prospective, community-based study to track changes in adenoma detection by individual physicians over time and to determine the effectiveness of targeted educational interventions. Methods: We prospectively collected information on 47,253 screening colonoscopies in average-risk individuals 50 years and older performed by a community-based practice in the Twin Cities of Minnesota. During a period of 3 years, 5 specific interventions were implemented; each was designed to improve adenoma detection rates. Controlling for patient-related and procedure-related factors, rates of adenoma detection and 3-year trends for individual physicians were plotted, and intraclass correlation coefficients were calculated. Generalized estimating equations were used to identify factors associated with detection of adenomas and polyps. Results: At least 1 polyp and 1 adenoma were found in 36% and 22% of examinations, respectively. Adenoma detection rates by endoscopists ranged from 10%-39%. There was no significant improvement during the study period despite planned, systematic interventions. Factors associated with adenoma detection included age of the patient (odds ratio [OR], 1.02; 95% confidence interval [CI], 1.02-1.02), male sex (OR, 1.53; 95% CI, 1.34-1.74), and adequate preparation quality (OR, 2.26; 95% CI, 1.64-3.12). Conclusions: The detection of adenomas by individual physicians during a 3-year period varied and did not appear to change between individual endoscopists, despite planned, systematic interventions. This indicates that other targeted interventions might be required to improve adenoma detection rates among experienced, community gastroenterologists.