Quality of colonoscopy withdrawal technique and variability in adenoma detection rates (with videos)

Gastrointest Endosc. 2011 Jul;74(1):128-34. doi: 10.1016/j.gie.2011.03.003. Epub 2011 Apr 30.


Background: Studies suggest that endoscopist-related factors such as colonoscopy withdrawal time are important in determining the adenoma detection rate (ADR).

Objective: To determine the importance of withdrawal technique in differentiating among endoscopists with varying ADRs.

Design: Prospective, multicenter study.

Setting: Five academic tertiary-care medical centers.

Participants: This study involved 11 gastroenterology faculty endoscopists.

Intervention: A retrospective review of screening colonoscopies was performed to categorize endoscopists into low, moderate, and high ADR groups. Video recordings were randomly obtained for each endoscopist on 20 (10 real, 10 sham) withdrawals during colonoscopies performed for average-risk colorectal cancer screening. Three blinded reviewers assigned withdrawal technique scores (total of 75 points) on 110 video recordings. A separate reviewer recorded withdrawal times.

Main outcome measurements: Withdrawal technique scores and withdrawal times.

Results: Mean (± standard deviation [SD]) withdrawal technique scores were higher in the moderate (62 ± 2.5) and high (59.5 ± 3) ADR groups compared with the low (40.8±3) ADR group (P = .002). Mean (± SD) withdrawal times were 6.3 ± 1.8 minutes (low ADR), 10.2 ± 1.5 minutes (moderate ADR), and 8.2 ± 1.8 minutes (high ADR) (P = .29). A comparison of the withdrawal times and technique scores of the two individual endoscopists with the lowest and highest ADRs did not find a significant difference in withdrawal times (6.6 ± 1.7 vs 7.4 ± 1.7 minutes) (P = .36) but did find a nearly 2-fold difference in technique scores (36.2 ± 9 vs 62.8 ± 9.9) (P = .0001).

Limitations: Not adequately powered to detect small differences in withdrawal times.

Conclusion: Withdrawal technique is an important indicator that differentiates between endoscopists with varying ADRs. It is possible that withdrawal technique is equal to, if not more important than, withdrawal time in determining ADRs.

Publication types

  • Multicenter Study
  • Video-Audio Media

MeSH terms

  • Adenoma / diagnosis*
  • Adult
  • Aged
  • Colonoscopy / methods
  • Colonoscopy / standards*
  • Colorectal Neoplasms / diagnosis*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Retrospective Studies
  • Time Factors