Developing risk prediction models for type 2 diabetes: a systematic review of methodology and reporting

Table 5 Evaluating performance of risk prediction models^a

Parameter	Number of studies (%)
Validation
Apparent	30 (77%)
Internal	15 (38%)
Bootstrapping	2 (5%)
Jack-knifing	1 (3%)
Random split sample	10 (26%)
Cross-validation	2 (5%)
Temporal	3 (8%)
External	21 (54%)
Performance metrics^b
Discrimination
C-statistic	39 (100%)
D-statistic	1 (3%)
Calibration^c	10 (26%)
Hosmer-Lemeshow statistic	8 (21%)
Calibration plot	2 (5%)
Classification
Reclassification (NRI)	2 (5%)
Other (for example, sensitivity, specificity)	31 (79%)

^aNRI,- Net Reclassification Index; ^bstudies can report more than one performance metric; ^ccalibration assessed on the basis of the development cohort in 10 studies and in the validation cohorts in 2 studies.

ISSN: 1741-7015