Screening Colonoscopy Withdrawal Time Threshold for Adequate Proximal Serrated Polyp Detection Rate

Area of Science:

• Gastroenterology
• Endoscopy Quality Improvement

Background:

• Current guidelines recommend a mean withdrawal time (MWT) of ≥6 minutes for adequate adenoma detection rate (ADR).
• Adenoma detection rate (ADR) correlates with proximal serrated polyp detection rate (PSP-DR), another key quality indicator for screening colonoscopy.
• The direct impact of measured withdrawal time on PSP-DR has not been extensively studied.

Purpose of the Study:

• To examine the relationship between mean withdrawal time (MWT), adenoma detection rate (ADR), and proximal serrated polyp detection rate (PSP-DR).
• To identify a specific withdrawal time threshold associated with improved ADR and PSP-DR.

Main Methods:

• Retrospective analysis of endoscopy and pathology data from average-risk screening colonoscopies.
• Utilized natural language processing to determine polyp location and histology.
• Calculated ADR and PSP-DR per endoscopist; MWT derived from procedures without polyp resection.

Main Results:

• A MWT of 11 minutes was the first statistically significant time point for increased PSP-DR (14.2%, p=0.01).
• Compared to MWT <11 minutes, MWT ≥11 minutes showed significant increases in adenoma detection (OR 1.65) and proximal serrated polyp detection (OR 1.81).
• ADR showed a strong linear correlation with MWT (R=0.76, p<0.001), while PSP-DR had a less robust linear correlation (R=0.42, p=0.043).

Conclusions:

• A MWT of 11 minutes significantly enhanced both ADR and PSP-DR in average-risk screening colonoscopies.
• Findings suggest that exceeding 11 minutes of withdrawal time may be necessary to optimize these critical colonoscopy quality metrics.