ACS-NSQIP risk calculator predicts cohort but not individual risk of complication following colorectal resection

Abstract Objective Compare the ACS-NSQIP risk calculator with institutional risk for colorectal surgery. Methods Actual and predicted outcomes were compared for both cohort and individuals. Results For the cohort, the risk calculator was accurate for 7/8 outcomes; there were more serious complications than predicted (19.4 vs 14.7%, p  Patients with better outcomes than predicted were current smokers (OR 4.3 95% CI 1.2–15.4), ASA ≥ 3 (OR 10.4, 95% CI 2.8–39.2), underwent total/subtotal colectomy (OR 3.5, 95% CI 1.1–12.2) or operated by Surgeon 2 (OR 2.9, 95% CI 1.4–11.6). Patients with serious complications who had low predicted risk had low ASA (OR 10.5, 95% CI 1.3–82.6), and underwent operation by Surgeon 2 (OR 11.8, 95% CI 2.5, 55.2). Limitations Single center study, sample size may bias subgroup analyses. Conclusions The ACS NSQIP calculator did not predict outcome better than sample risk.