Table 4.

Mean (95% confidence interval) performance of model in the internal and temporal validation cohort

Statistic	Internal validation	Temporal validation
D statistic*	0.111 (0.110-0.113)	0.024 (0.022-0.026)
Harrell's C*	0.851 (0.803-0.965)	0.777 (0.823-0.979)
R2(%)†	0.302 (0.298-0.306)	0.159 (0.155-0.162)
Brier‡	0.049 (0.047-0.051)	0.096 (0.094-0.098)

*A measure of discrimination. Higher values indicate better discrimination

^†Measures explained the degree of fit between the cohort and the fitted model. Higher values indicate better fit

^‡A measure of calibration. Lower values indicate better calibration