Data Sheet 1_Explainable random forest–SHAP framework for Montreal phenotype–stratified prediction of one-year complications in Crohn’s disease.pdf

Phenotype-stratified and non-linear associations between CDAI and complication risk were further analyzed within the Montreal framework.</p>Results<p>Within one year after discharge, bowel resection, perianal complications, and abdominal complications occurred in 70 (18.9%), 142 (38.4%), and 84 (22.7%) patients, respectively. Random Forest showed the most consistent overall performance, achieving an AUROC of 0.86 (95% CI, 0.82–0.90) for bowel resection, 0.71 (95% CI, 0.64–0.78) for perianal complications, and 0.73 (95% CI, 0.69–0.78) for abdominal complications.

SHAP identified distinct predictors across outcomes: disease behavior, nutritional support therapy, and disease duration for bowel resection; prior perianal complications, extraintestinal manifestations, and CDAI for perianal complications; and prior abdominal complications, nutritional support therapy, and Montreal L3 phenotype for abdominal complications. Receipt of NST was interpreted as a clinical marker of nutritional depletion and greater disease burden rather than as a causal risk factor.

Montreal-based stratification revealed marked heterogeneity, with isolated small-bowel disease associated with higher risks of bowel resection and abdominal complications, and isolated colonic disease with the highest burden of perianal complications.</p>Conclusion<p>The interpretable RF–SHAP framework showed potential for Montreal phenotype–stratified prediction of one-year complication risk in CD and inform future evaluation of risk stratification and phenotype-informed management.</p>