Application of withdrawal-to-intubation ratio in assessing pattern and quality of colonoscopic intervention: a retrospective cohort analysis

Background Withdrawal-to-intubation ratio (WIR) is a novel time-related indicator for colonoscopy quality. The clinical pattern of WIR for various colonoscopic interventions remains unclear. We herein performed this study to explore its patterns in stratified colonoscopy and confirm associated factors for detection of colorectal adenoma. Methods This was a single-center retrospective analysis between January 2024 and December 2025. Consecutive subjects who underwent colonoscopic examination or treatment were included. Time-related parameters, including cecum intubation time (CIT), colonoscopy withdrawal time (CWT) and WIR, were compared in various colonoscopic interventions. Factors related to adenoma detection rate (ADR) were analyzed with univariate and multivariate regression, with CWT≥360 s (6 min) and WIR≥1.8 regarded as exploratory cut-off values. Results 3725 subjects were included, with 52.1% male and 47.9% female. The cecum intubation rate was 99.4% once luminal stenosis excluded. The overall ADR was 32.8%. The median CIT, CWT and WIR were 190 s, 268 s and 1.43, respectively. The average WIR (1.22 vs. 2.00, P < 0.001) and CWT (213.0 vs. 355.4 s, P < 0.001) were significantly different between endoscopic examination and treatment. Logistic regression analysis revealed that male sex, age ≥ 60 years, use of hood and image-enhanced endoscopy, CWT ≥ 360 s and WIR ≥ 1.8 were significant factors associated with adenoma detection. Conclusions Our findings suggest that WIR would be a reliable indicator for stratification and quality control of colonoscopic interventions.