External validation of prognostic models among cancer patients undergoing emergency colorectal surgery

BACKGROUND: The aim of this study was to evaluate the predictive accuracy of different scoring systems on patients undergoing emergency colorectal surgery. METHODS: The Acute Physiology and Chronic Health Evaluation II or III, the Simplified Acute Physiology Score II, the Mortality Probability Model II, and the Colo-rectal POSSUM scoring systems were applied to 102 patients who underwent colorectal resection for cancer. Validation of scoring systems was tested by assessing calibration and discrimination. Calibration was assessed using Hosmer-Lemeshow goodness-of-fit test and the corresponding calibration curves. Evaluation of the discriminative capability of both models was performed using receiver-operating characteristic curve analysis. RESULTS: Overall, 17 deaths occurred. The Simplified Acute Physiology Score II showed good calibration (x(2) = 1.079, P = .982) and discrimination (areas under the receiver-operating characteristic curve .83). CONCLUSIONS: These data suggest that the SAPS II scoring system was accurate in predicting outcome for patients undergoing emergency colorectal surgery.