Summary of performance measures reported in the 41 development studies.

Overview of performance measures reported by ≥2 studies. At least one performance measure was required for inclusion; most studies reported more than one. A summary of measures per study is given in Table S2, and the measures reported for each model are in Table S3. The heterogeneity of the studies precludes direct comparison of model performance.AUC = area under the curve; ideal = 1.0 and chance = 0.5.R2 = coefficient of determination; the proportion of variability that is accounted for by the model. ideal = 1.0.H-L p = Hosmer-Lemeshow p value; any non-significant value indicates acceptable calibration.% correct; ideal = 1.0 and chance ≈ %survival2.PPV = positive predictive value; ideal = 1.0 and chance related to prevalence and cut-off.NPV = negative predictive value; ideal = 1.0 and chance related to prevalence and cut-off.sensitivity; ideal = 1.0 and chance related to prevalence.specificity; ideal = 1.0 and chance related to prevalence.range = the range of probabilities generated by the model.Note that performance measures of unvalidated models may be overestimated.