The impact of exclusion criteria on a physician’s adenoma detection rate

BackgroundThe adenoma detection rate (ADR) is a validated and widely used measure of colonoscopy quality. There is uncertainty in the published literature as to which colonoscopy examinations should be excluded when measuring a physician’s ADR.ObjectiveTo examine the impact of varying the colonoscopy exclusion criteria on physician ADR.DesignWe applied different exclusion criteria used in 30 previous studies to a dataset of endoscopy and pathology reports. Under each exclusion criterion, we calculated physician ADR.SettingA private practice colonoscopy center affiliated with the University of Illinois College of Medicine.PatientsData on 20,040 colonoscopy examinations performed by 11 gastroenterologists from July 2009 to May 2013 and associated pathology notes.Main Outcome MeasurementsADRs across all colonoscopy examinations, each physician’s ADR, and ADR ranking.ResultsThere were 28 different exclusion criteria used when measuring the ADR. Each study used a different combination of these exclusion criteria. The proportion of all colonoscopy examinations in the dataset excluded under these combinations of exclusion criteria ranged from 0% to 92.2%. The mean ADR across all colonoscopy examinations was 39.1%. The change in mean ADR after applying the 28 exclusion criteria ranged from −5.5 to +3.0 percentage points. However, the exclusion criteria affected each physician’s ADR relatively equally, and therefore physicians’ rankings via the ADR were stable.LimitationsADR assessment was limited to a single private endoscopy center.ConclusionThere is wide variation in the exclusion criteria used when measuring the ADR. Although these exclusion criteria can affect overall ADRs, the relative rankings of physicians by ADR were stable. A consensus definition of which exclusion criteria are applied when measuring ADR is needed.