Table 3  Model discrimination in derivation and validation cohorts
Model  Derivation cohort  Validation cohort
Model  AUROc (95% CI)  Brier score  AUROc (95% CI)  Brier score
4C Mortality Score  0.786 (0.781 to 0.790)  0.170  0.767 (0.760 to 0.773)  0.171
Machine learning comparison*  0.796 (0.786 to 0.807)  0.191  0.779 (0.772 to 0.785)  0.197
AUROC=area under receiver operator curve; CI=confidence interval.
*Gradient boosting decision tree (XGBoost).