Table 1

Characteristics of rheumatoid arthritis (RA) index cases from the investigated samples


Sample 1 (n = 100)
Sample 2 (n = 100)
Sample 3 (n = 265)

Females (%)
87
90
86
Mean age of disease onset (years) (±standard deviation)
32 (±10)
31 (±6)
30 (±9)
Mean disease duration (years) (±standard deviation)
18 (±7)
16 (±8)
8 (±7)
RA patients with bone erosions (%)
90
79
72
RA patients seropositive for rheumatoid factor (%)
81
76
73
RA patients carrying at least one HLA-DRB1 shared epitope allele (%)
78
80
Not available

n, number of cases.

Jacq et al. Arthritis Research & Therapy 2007 9:R63   doi:10.1186/ar2221