Ó³»­´«Ã½

UNLABELLED: Serrated polyps (SP) are precursors for colorectal cancer and contribute disproportionately to postcolonoscopy cancers. Leveraging three U.S. cohorts (43,974 women and 5,322 men), we developed prediction models for high-risk SPs (sized ≥10 mm or ≥3) among individuals undergoing their first colonoscopy screening. We then validated the model in the Partners Colonoscopy Cohort (51,203 women and 39,077 men). We evaluated discrimination and calibration using the C-statistic and Hosmer-Lemeshow test, respectively. The age and family history model generated a C-statistic [95% confidence interval (CI)] of 0.57 (0.56-0.58) in women and 0.58 (0.55-0.61) in men. Further inclusion of smoking, alcohol, and body mass index (the simple model) increased the C-statistic (95% CI) to 0.68 (0.67-0.69) in women and 0.68 (0.66-0.71) in men (all P < 0.001). Adding more predictors did not provide much incremental predictivity. In the validation cohort, moderate discrimination was observed in both women (0.60, 0.58-0.61) and men (0.60, 0.59-0.62). Notably, the simple model also yielded similar C-statistics for a composite endpoint of SPs and high-risk conventional adenomas (women, 0.62, 0.62-0.63; men, 0.63, 0.61-0.64). The model was adequately calibrated in both sets of cohorts. In summary, we developed and externally validated a simple prediction model based on five major risk factors for high-risk SPs that may be useful for healthy lifestyle recommendations and tailored colorectal cancer screening.PREVENTION RELEVANCE: On the basis of four prospective studies in the United States, we developed and externally validated a simple risk prediction model for high-risk SPs in the setting of colonoscopy screening. Our model showed moderate discriminatory accuracy and has potential utility for individualized risk assessment, healthy lifestyle recommendations, and tailored colorectal cancer prevention.