Table 2

Diagnostic accuracy and predictive value for CTCA

	Pretest probability	No	TP	FP	TN	FN	Sens	Spec	PPV	NPV	Accuracy	+LR	−LR
Per patient		42	23	2	17	0	100	90	92	100	95	9.50	0
Low	16	7	3	1	3	0	100	75	75	100	86	4.00	0
Intermediate	52	22	13	0	9	0	100	100	100	100	100	NA	0
High	87	13	7	1	5	0	100	83	100	88	92	6.00	0
Per vessel	–	168	49	6	110	3	94	95	89	95	95	18.22	0.06
Low	–	28	7	3	17	1	88	85	70	94	86	5.83	0.15
Intermediate	–	88	28	2	57	1	97	97	93	98	97	28.48	0.04
High	–	52	14	1	36	1	93	97	93	97	96	34.53	0.07

FN, false negative; FP, false positive; LR, likelihood ratio; NA, not available; NPV, negative predictive value; PPV, positive predictive value; Sens, sensitivity; Spec, specificity; TN, true negative; TP, true positive.