Table 3. Baseline characteristics of ACPA-positive/Rheumatoid Factor-positive patients that progressed to RA and did not progress to RA during 2 year follow-up.

Patient characteristic	Convertors (N=12)		Non-convertors (N=6)		p-value
Age in years, mean (SD)	45	(15)	49.8	(11)	0.50
Female sex, n (%)	9 / 12	(75)	5 / 6	(83)	0.69
Family history of RA, n (%)	4 / 12	(33)	0 / 6	(0)	0.11
68-TJC, median (IQR)	5.0	(3–8)	5.5	(2–9)	0.87
CRP
Elevated CRP (>10 mg/L), n (%)	5 / 12	(42)	2 / 6	(33)	0.73
CRP-level, median (IQR)	4.7	(3–12)	4.2	(3–6)	0.32
IgM-RF level (IU/mL), mean (SD)	76.6	(77)	79.2	(64)	0.93
ACPA-level (U/mL), mean (SD)	222.8	(125)	211.0	(141)	0.87
MRI positive for inflammation
Any inflammation present, n (%)	9 / 10	(90)	5 / 6	(83)	0.70
Total RAMRIS score, median (IQR)	5.8	(3–19)	5.8	(4–11)	0.36

Symptoms were noted by rheumatologists as reported by the patients.

Glossary: ACPA = anti-citrullinated peptide antibody; CRP = c-reactive protein; IgM-RF = immunoglobulin M rheumatoid factor; IQR = interquartile range; MRI = magnetic resonance imaging; RA = rheumatoid arthritis; RAMRIS = Rheumatoid Arthritis MRI scoring system; SD = standard deviation; TJC = tender joint count.