Table 4.

Measures of performance improvement with 95% confidence intervals adding novel CAC distribution measures to Framingham risk score and CAC score categories for the prediction of major coronary heart disease events

Marker	AUC (C-statistic)	Relative IDI
Number of coronary segments with CAC	0.79 (0.72, 0.86)	0.20 (0.06, 0.38)
Number of coronary arteries with CAC	0.80 (0.73, 0.87)	0.14 (0.06, 0.23)
Proximal dominant coronary artery CAC	0.79 (0.71, 0.87)	0.14 (0.09, 0.20)

^*AUC (C-statistic) for Framingham risk score 0.72 (0.64,0.80) and for multivariable model with CAC categories and Framingham risk score 0.77 (0.69, 0.85)