Table 3.

The reclassification performance and improvement in discrimination by the three aging metrics incorporating cognitive and physical function^a

Aging metrics	Delta C-statistic	P value	IDI	P value	NRI	P value
CHARLS
CI-PF	0.008	0.017	0.011	< 0.001	0.211	< 0.001
FI	0.006	0.130	0.009	< 0.001	0.155	< 0.001
MCR	0.0003	0.843	0.001	0.035	−0.027	0.441
NHANES
CI-PF	0.021	< 0.001	0.033	< 0.001	0.568	< 0.001
FI	0.029	< 0.001	0.043	< 0.001	0.332	< 0.001
MCR	0.003	0.033	0.007	< 0.001	0.125	< 0.001

IDI integrated discrimination improvement, NRI net reclassification index, CHARLS China Health and Retirement Longitudinal Study, CI-PF cognitive impairment and physical frailty, FI frailty index, MCR Motoric Cognitive Risk syndrome, NHANES National Health and Nutrition Examination Survey

Notes: ^aWe calculated the IDI and continuous NRI using the R package “PredictABEL”, in comparison to that of the model with age and sex