Table 4

Percentage true positives and negatives, and false positives and negatives for measurement properties of spinal mobility, with radiographic damage set as the gold standard”

	Gold standard defined as mSASSS >0				Gold standard defined as mSASSS >3				Gold standard defined as mSASSS >6
	True positive	True negative	False positive	False negative	True positive	True negative	False positive	False negative	True positive	True negative	False positive	False negative
BASMI, Bath Ankylosing Spondylitis Metrology Index.
Chest expansion (cm)	48	22	8	22	39	35	8	18	34	45	10	11
Finger to floor distance (cm)	44	24	6	26	38	31	12	18	35	39	10	16
Occiput to wall distance (cm)	41	24	12	29	38	37	7	18	34	44	11	11
Tragus to wall distance (cm)	41	23	7	29	38	33	10	19	28	47	8	17
Modified Schober (cm)	33	28	2	37	32	39	5	24	26	53	2	19
Cervical rotation (degrees)	44	22	8	26	26	40	3	31	23	49	6	22
Lateral spinal flexion (cm)	60	21	8	11	44	34	8	14	35	45	8	12
Intermalleolar distance (cm)	36	25	5	34	30	32	12	27	28	39	16	17
BASMI	53	24	5	18	44	34	9	13	37	45	9	9