Table 3.

Sensitivity, specificity, PPV and NPV of IBP for the diagnosis of axSpA

Assessor	IBP according to…	Sensitivity, % (95% CI)	Specificity, % (95% CI)	PPV (95% CI)	NPV (95% CI)	LR+ (95% CI)	LR− (95% CI)
Blinded rheumatologist	Global evaluation	81.1 (75.4 to 86.8)	43.9 (37.3 to 50.7)	53.9 (48.0 to 59.8)	74.2 (66.8 to 81.7)	1.4 (1.3 to 1.7)	0.4 (0.3 to 0.6)
	Calin’s criteria	79.4 (73.5 to 85.4)	25.1 (19.6 to 31.3)	46.1 (40.6 to 51.9)	60.2 (50.0 to 70.2)	1.1 (1.0 to 1.2)	0.8 (0.6 to 1.2)
	Berlin criteria	81.1 (75.4 to 86.8)	32.3 (26.2 to 38.6)	49.2 (43.3 to 55.0)	67.9 (58.7 to 76.7)	1.2 (1.1 to 1.3)	0.6 (0.4 to 0.8)
	ASAS criteria	74.4 (68.1 to 80.8)	39.5 (33.0 to 46.1)	49.8 (43.8 to 55.8)	65.7 (57.3 to 73.4)	1.2 (1.1 to 1.4)	0.6 (0.5 to 0.9)
Diagnosing rheumatologist	Global evaluation	90.0 (85.6 to 94.4)	58.7 (52.1 to 65.2)	63.8 (57.8 to 69.7)	87.9 (81.9 to 92.7)	2.2 (1.9 to 2.6)	0.2 (0.1 to 0.3)
	Calin’s criteria	85.0 (79.8 to 90.2)	26.9 (21.4 to 33.0)	48.4 (42.8 to 54.1)	69.0 (58.4 to 78.2)	1.2 (1.1 to 1.3)	0.6 (0.4 to 0.8)
	Berlin criteria	83.9 (78.5 to 89.3)	44.8 (38.2 to 51.6)	55.1 (49.0 to 61.1)	77.5 (69.7 to 84.4)	1.5 (1.3 to 1.7)	0.4 (0.2 to 0.5)
	ASAS criteria	83.9 (78.5 to 89.3)	35.4 (29.2 to 41.8)	51.2 (45.3 to 57.0)	73.2 (64.2 to 80.8)	1.3 (1.2 to 1.5)	0.5 (0.3 to 0.7)
Patient	Calin’s criteria	75.1 (68.8 to 81.5)	20.6 (15.6 to 26.3)	43.3 (37.7 to 49.0)	50.6 (39.8 to 61.0)	0.9 (0.8 to 1.1)	1.2 (0.8 to 1.7)
	Berlin criteria	86.4 (81.4 to 91.5)	18.3 (13.5 to 23.7)	46.1 (40.6 to 51.6)	62.5 (50.0 to 74.0)	1.1 (1.0 to 1.2)	0.7 (0.5 to 1.2)
	ASAS criteria	74.0 (67.6 to 80.5)	31.1 (25.0 to 37.6)	46.5 (40.5 to 52.4)	59.7 (50.5 to 68.7)	1.1 (0.9 to 1.2)	0.8 (0.6 to 1.1)

ASAS, Assessment of SpondyloArthritis international Society; IBP, inflammatory back pain; LR, likelihood ratio; NPV, negative predictive value; PPV, positive predictive value; SpA, spondyloarthritis; axSpA, axial spondyloarthritis.