A comparison of 9 minutes colonoscopy withdrawal time and 6 mins colonoscopy withdrawal time: A systematic review and meta-analysis.

INTRODUCTION The optimal colonoscopy withdrawal time is still a controversial topic. While several studies demonstrate that longer withdrawal time improves adenoma detection rate, others have contradicted these findings. METHODS Three independent reviewers performed a comprehensive review of all original articles published from inception to January 2021 and included studies reporting comparison of the two cohorts - (a) ≥6 but less than 9 minutes colonoscopy withdrawal time (CWT) and (b) ≥ 9 minutes of CWT. The outcome measures were the following: (1) Adenoma Detection Rate (ADR), (2) Advanced Adenoma Detection Rate, (3) Sessile Serrated Adenoma Detection Rate (SDR). The meta-analysis was performed and the statistics were 2-tailed. RESULTS A total of seven studies met the inclusion criteria after a thorough search of the literature was completed. The analysis revealed that ≥ 9 minutes of CWT had significantly higher odds of Adenoma Detection as compared to 6-9 mins of CWT ((OR 1.54, 95% CI 1.30 - 1.82; I2 =93.7). Additionally, a significantly higher odds of sessile serrated adenoma detection (OR 1.68, 95% CI 1.28 - 2.22; I2 =0) and a trend towards higher odds of advanced adenoma detection (OR 1.38, 95% CI 0.98 - 1.95, I2 =90) were seen with CWT of at least 9 minutes when compared with 6-9 mins of CWT. CONCLUSION This systematic review and meta-analysis analysis provides further evidence that at least 9 minutes CWT cohort had significantly higher ADR and SDR as compared to the at least 6 minutes but less than 9 minutes cohort.