Table 3

Comparisons of AUCs, IDI and NRI for risk factors and intra-aortic PP

Models	AUC	95% CI	P value for AUCs	IDI				Category-free NRI
Models	AUC	95% CI	P value for AUCs	Absolute IDI	95% CI	P value	Relative IDI (%)	Event (%)	Nonevent (%)	Total NRI	95% CI	P value
Risk factors	0.615	0.590 to 0.641	reference
Aortic PP	0.630	0.604 to 0.657	0.243	−0.003	−0.047 to 0.007	0.547	0.933	−0.1	−1.1	−0.013	−0.0474 to 0.0219	0.470
Risk factors+Aortic PP	0.644	0.617 to 0.670	<0.001*	0.0108*	0.0058 to 0.0158*	<0.001*	1.227*	5.1*	−8.7*	0.0499*	0.0226 to 0.0773*	<0.001*
Risk factors+Aortic PP			0.053†	0.0137†	0.008 to 0.019†	<0.001†	1.3072†	8.5†	−2.3†	0.063†	0.0334 to 0.0919†	<0.001†

Risk factors: age ≥ 60, renal dysfunction, female sex.
*Comparison with the ROC curves of risk factors (reference group).
†Comparison with the ROC curves of central PP.
AUC, area under the curve; IDI, integrated discrimination improvement; NRI, net reclassification improvement; PP, pulse pressure ; ROC, receiver operating characteristics.