Validation of post-colonoscopy colorectal cancer (PCCRC) cases reported at national level following local root cause analysis: REFLECT study.

Our single-centre study shows, after local analysis, there was misclassification of PCCRCs identified from a population-based registry. The degree of such error will vary between registries. Most PCCRCs occurred in cases of sub-optimal examination as indicated by poor photodocumentation. Effective mechanisms to feedback root cause analyses are critical for quality improvement.