Table 3. Effect of Variables on Model Prediction Accuracy and Risk Reclassification.

Model	Included Variable	IDI Index (95% CI)	P	Model Prediction (C-Index)
Model A	FRS	-	-	0.66
Model B	FRS + CACS	0.19 (0.09–0.28) vs. Model A	< 0.001*	0.72
Model C	FRS + stenosis degree	1.62 (1.42–1.83) vs. Model A	< 0.001*	0.83
		1.43 (1.24–1.63) vs. Model B	< 0.001*
Model D	FRS + stenosis degree + CACS	1.63 (1.43–1.83) vs. Model A	< 0.001*	0.83
		1.45 (1.26–1.63) vs. Model B	< 0.001*
		0.01 (−0.02–0.04) vs. Model C	0.431
Model E	FRS + stenosis degree + plaque type	1.69 (1.50–1.89) vs. Model A	< 0.001*	0.85
		1.51 (1.31–1.71) vs. Model B	< 0.001*
		0.08 (0.01–0.14) vs. Model C	0.023*
		0.06 (−0.02–0.14) vs. Model D	0.117
Model F	FRS + stenosis degree + plaque type + CACS	1.76 (1.56–1.95) vs. Model A	< 0.001*	0.85
		1.57 (1.39–1.75) vs. Model B	< 0.001*
		0.14 (0.05–0.23) vs. Model C	0.003*
		0.13 (0.04–0.21) vs. Model D	0.004*
		0.06 (−0.01–0.12) vs. Model E	0.067

^*p < 0.05. IDI = integrated discrimination improvement