The detection of premalignant colon polyps during colonoscopy is stable throughout the workday

Recent studies have shown that colonoscopic polyp detection decreases as the workday progresses. This may reflect time-dependent factors such as colonoscopist fatigue and decreased colon cleanliness, which can be addressed through adaptations in colonoscopy practice.To test for time-of-day differences in adenomatous polyp (AP) and sessile serrated polyp (SSP) detection in a practice that uses split-dose bowel preparation and moderated daily colonoscopist procedure loads.Retrospective chart review.Community-based, group gastroenterology practice.This study involved 2439 patients undergoing surveillance or screening colonoscopy.Colonoscopy.Detection rate of all premalignant polyps (PMPs), and of APs and SSPs, individually.A total of 1183 PMPs were identified in 1486 eligible patients (mean PMP/colonoscopy = 0.80; PMP detection rate = 47%). In univariate and multivariate analyses, PMP detection as well as detection of APs or SSPs individually did not vary significantly in relation to the hour of the day. In a binary comparison of morning (am) versus afternoon (pm) procedures, the total polyp detection rate was 67% and 66%, respectively. For PMPs, APs, SSPs, and hyperplastic polyps (HPs), the am and pm detection rates were 46% and 47%, 41% and 44%, 8% and 8%, and 27% and 24%, respectively. Bowel preparation quality was independent of time of day and was rated excellent or good in 86% to 87% of cases.Retrospective, nonrandomized study.Stable PMP, AP, SSP, and HP detection rates throughout the workday occur under certain practice conditions, including the use of split-dose bowel preparation and/or moderated daily colonoscopist procedure loads.