The association of colonoscopy quality indicators with the detection of screen-relevant lesions, adverse events, and postcolonoscopy cancers in an asymptomatic Canadian colorectal cancer screening population

BackgroundAlthough several quality indicators of colonoscopy have been defined, quality assurance activities should be directed at the measurement of quality indicators that are predictive of key screening colonoscopy outcomes.ObjectiveThe goal of this study was to examine the association among established quality indicators and the detection of screen-relevant lesions (SRLs), adverse events, and postcolonoscopy cancers.DesignHistorical cohort study.SettingCanadian colorectal cancer screening center.PatientsA total of 18,456 asymptomatic men and women ages 40 to 74, at either average risk or increased risk for colorectal cancer because of a family history, who underwent a screening colonoscopy from 2008 to 2010.Main Outcome MeasurementsUsing univariate and multivariate analyses, we explored the association among procedural quality indicators and 3 colonoscopy outcomes: detection of SRLs, adverse events, and postcolonoscopy cancers.ResultsThe crude rates of SRLs, adverse events, and postcolonoscopy cancers were 240, 6.44, and .54 per 1000 colonoscopies, respectively. Several indicators, including endoscopist withdrawal time (OR, 1.3; 95% CI, 1.2-1.4) and cecal intubation rate (OR, 13.9; 95% CI, 1.9-96.9), were associated with the detection of SRLs. No quality indicator was associated with the risk of adverse events. Endoscopist average withdrawal time over 6 minutes (OR, .12; 95% CI, .002-.85) and SRL detection rate over 20% (OR, .17; 95% CI, .03-.74) were associated with a reduced risk of postcolonoscopy cancers.LimitationsSingle-center study.ConclusionQuality assurance programs should prioritize the measurement of endoscopist average withdrawal time and adenoma (SRL) detection rate.