Figure 3 Figure 3 The receiver operating characteristic (ROC) Curves of ISS and NISS for predicting mortality in the whole population (749 patients). There were no significant differences between scores. Cut off points were 22 for ISS (sensitivity 90.5%, specificity 95.4%, AUC 0.962, 95% CI 0.945 to 0.974) and 22 for NISS (sensitivity 100%, specificity 88.7 %, AUC 0.950, 95% CI 0.931 to 0.964).