Table 3.

Results for CRP-positive and CRP-negative patients

	CRP-positive patients				CRP-negative patients
	Baseline value	Adjusted mean changes (95% CI)		P -value	Baseline value	Adjusted mean changes (95% CI)		P -value
		<4 years	≥4 years			<4 years	≥4 years
		n = 30	n = 15			n = 26	n = 37
BASDAI	5.4	3.3 (2.7, 4.0)	2.4 (1.5, 3.3)	0.11	5.5	3 (2.3, 3.7)	1.3 (0.7, 1.9)	0.001
BASFI	4.2	2.4 (1.8, 3.0)	1.8 (0.9, 2.7)	0.23	4.5	2.4 (1.8, 3.1)	0.9 (0.4, 1.5)	0.001
BASMI	1.5	0.1 (−0.3, 0.4)	0.4 (−0.1, 0.9)	0.30	2.0	0.5 (0, 1)	−0.3 (−0.6, 0.1)	0.01
ASDAS	3.6	1.9 (1.6, 2.2)	1.5 (1.1, 1.9)	0.07	2.8	1.3 (1, 1.6)	0.6 (0.3, 0.8)	0.001
CRP*	13.8	2.7 (2.2, 3.3)	2.1 (1.5, 3)	0.20	3.6	1.2 (1, 1.5)	1.2 (1, 1.4)	0.86
MRI SIJ	6.6	4.6 (3.6, 5.7)	3.5 (2, 4.9)	0.19	3.8	2.5 (1.8, 3.2)	2.5 (1.9, 3.1)	0.96

*Log-transformed CRP results were back-transformed; P-value <0.05 was taken to indicate statistically significant differences between two groups; adjusted mean changes from baseline under treatment with etanercept or adalimumab (95% CI). Outcome differences were adjusted for baseline status (see Methods). BASDAI, Bath ankylosing spondylitis disease activity index; BASFI, Bath ankylosing spondylitis functional index; BASMI, Bath ankylosing spondylitis metrology index; ASDAS, ankylosing spondylitis disease activity score; CRP, C-reactive protein in mg/l; MRI, magnetic resonance imaging; SIJ, sacroiliac joint.