Table 6

Predictive ability, reclassification and discrimination of all-cause dementia and Alzheimer’s disease by hippocampal atrophy and accumulated numbers of grey matter atrophy, 2012–2017

	Harrell’s c-statistics	P value for Harrell’s c-statistics difference (vs basic model)	Continuous NRI (95% CI)	P value for continuous NRI (vs basic model)	IDI (95% CI)	P value for IDI (vs basic model)
All-cause dementia
Basic model*	0.748	Reference
Basic model* +hippocampal atrophy	0.763	0.24	0.617 (0.431 to 0.804)	<0.001	0.011 (0.004 to 0.017)	<0.001
Basic model* +accumulated numbers of grey matter atrophy	0.775	0.08	0.508 (0.317 to 0.699)	<0.001	0.020 (0.012 to 0.029)	<0.001
Alzheimer’s disease
Basic model*	0.765	Reference
Basic model* +hippocampal atrophy	0.785	0.15	0.610 (0.395 to 0.825)	<0.001	0.011 (0.004 to 0.020)	0.004
Basic model* +accumulated numbers of grey matter atrophy	0.802	0.02	0.465 (0.245 to 0.686)	<0.001	0.022 (0.011 to 0.032)	<0.001

*The basic model included age, sex, education status, systolic blood pressure, antihypertensive medication, diabetes mellitus, serum total cholesterol, body mass index, ECG abnormalities, cerebrovascular lesions on MRI, smoking habits, alcohol intake, regular exercise and the total brain volume-to-intracranial volume ratio.
IDI, integrated discrimination improvement; NRI, net reclassification improvement.