Table 2.

Diagnostic performance of temporal artery biopsy and ultrasound features for detecting giant cell arteritis.

		Clinical diagnosis			Performance [95% Confidence interval]
		GCA (n = 35)	Non-GCA (n = 43)	Total
Temporal Artery Biopsy	Positive	24	0	24	Sn: 0.69 [0.51;0.83] Sp: 1.00 [0.92;1.00] PPV: 1.00a NPV: 0.80 [0.71;0.86] AUC: 0.84 [0.75;0.94]
	Negative	11	43	54
Ultrasound Compression sign	Positive	22	9	31	Sn: 0.63 [0.45;0.79] Sp: 0.79 [0.64;0.94] PPV: 0.71 [0.57;0.82] NPV: 0.72 [0.62;0.81] AUC: 0.71 [0.59;0.83]b
	Negative	13	34	47
Ultrasound Halo-sign	Positive	16	5	21	Sn: 0.47 [0.30;0.65] Sp: 0.77 [0.53;0.92] PPV: 0.76 [0.58;0.88] NPV: 0.47 [0.37;0.57] AUC: 0.67 [0.55;0.80]
	Negative	18	16	34
Ultrasound Reduced flow	Positive	2	3	5	Sn: 0.06 [0.01;0.20] Sp: 0.93 [0.80;0.98] PPV: 0.40 [0.11;0.79] NPV: 0.55 [0.52;0.58] AUC: 0.49 [0.36;0.63]
	Negative	31	38	69

AUC area under the curve, PPV positive predictive value, N number, NPV negative predictive value, Sp Specificity, Sn Sensitivity.

^aNot possible to calculate due to division by zero.

^bSignificant difference between temporal artery biopsy and ultrasound (p = 0.048).