Table 3.

Discriminations of the RF-CL and CACS-CL models.

	AUC			IDI
	Statistic	95% CI	p value	PTP		Statisticb	p value
				Positivea	Negative
RF-CL model	0.782	0.750–0.819	0.0016	47%	21%	12%	<0.0001
CACS-CL model	0.856	0.823–0.892		54%	16%

AUC, area under the receiver operating characteristic curve; IDI, integrated discrimination improvement; RF-CL, risk factor-weighted clinical likelihood; CACS-CL, coronary artery calcium score-weighted clinical likelihood; CI, confidence interval; CAD, coronary artery disease.

^a A positive patient was defined as a patient who had obstructive CAD.

^b Compared with the RF-CL model, the IDI of the CACS-CL model = [P(CACS-CL | Positive) − P(RF-CL | Positive)] − [ P(CACS-CL | Negative) − P(RF-CL | Negative)].