Table 2 Univariate regression analysis between candidate covariates and radiographic progression. All variables are baseline values

Variable	MRI of wrist + MCP group (n = 89)			MRI of wrist-only group (n = 130)
Variable	Coefficient	Confidence interval	p Value	Coefficient	Confidence interval	p Value
Gender	−0.77	−3.71 to 2.17	0.60	−0.03	−1.91 to 1.85	0.97
Age	0.03	−0.06 to 0.10	0.55	0.01	−0.07 to 0.09	0.81
DAS28	0.02	−0.88 to 0.92	0.96	0.05	−0.63 to 0.73	0.90
Disease duration	0.13	−0.07 to 0.33	0.21	0.11	−0.03 to 0.25	0.15
CRP	0.01	−0.39 to 0.41	0.45	0.01	−0.01 to 0.03	0.31
SJC	−0.04	−0.26 to 0.18	0.68	−0.03	−0.19 to 0.13	0.70
TJC	−0.10	−0.28 to 0.08	0.26	−0.08	−0.23 to 0.05	0.21
HAQ	−0.42	−2.02 to 1.18	0.60	−0.07	−1.33 to 1.19	0.91
Patient global	0.00	−0.04 to 0.04	0.86	0.00	−0.04 to 0.04	0.92
Patient pain	0.01	−0.03 to 0.05	0.58	0.01	−0.03 to 0.05	0.58
Doctor global	−0.01	−0.07 to 0.05	0.71	−0.02	−0.06 to 0.02	0.47
ESR	0.04	−0.02 to 0.10	0.14	0.03	−0.01 to 0.07	0.11
Ever smoker	−0.39	−2.81 to 2.03	0.75	−0.10	−1.98 to 1.78	0.92
Anti-CCP	1.36	−1.08 to 3.80	0.27	1.53	−0.27 to 3.33	0.09
IgM RF	−1.06	−3.55 to 1.43	0.40	0.04	−1.88 to 1.96	0.96
IgA RF	−1.49	−3.85 to 0.87	0.21	−0.62	−2.42 to 1.18	0.49
HLA-DRB1-SE	1.29	−1.57 to 4.15	0.37	1.52	−0.72 to 3.76	0.18
School	−0.50	−1.74 to 0.74	0.42	−0.40	−1.38 to 0.58	0.42
MRI erosion score	1.07	0.55 to 1.59	<0.001	0.74	0.28 to 1.20	0.001
MRI synovitis score	0.32	0.04 to 0.60	0.03	0.19	−0.19 to 0.57	0.31
MRI bone oedema	0.75	0.55 to 0.94	<0.001	0.59	0.40 to 0.77	<0.001
TSS	0.25	0.07 to 0.43	0.01	0.15	0.03 to 0.27	0.02

CCP, cyclic citrullinated peptide (dichotomised value); CRP, C-reactive protein; DAS28, Disease Activity Score (28-joint count); ESR, erythrocyte sedimentation rate and four variables; HAQ, Health Assessment Questionnaire; MCP, metacarpophalangeal; MRI, magnetic resonance imaging; RF, rheumatoid factor (dichotomised value); SE, shared epitope; SJC, swollen joint count (0–28); TJC, tender joint count (0.28); TSS, Total Sharp Score.