Characteristics of the ESPOIR and Leiden Early Arthritis Clinic (EAC) cohorts of patients with rheumatoid arthritis genotyped for SPP1 rs9138 or rs4574
| Cohort | No of patients | No of sets of radiographs of hands and feet | Year of diagnosis | Follow-up (years) | Method of scoring | ICC | APCA-negative (%) | Age (years), mean±SD | Female patients, n (%) |
|---|---|---|---|---|---|---|---|---|---|
| ESPOIR | 652 | 1768 | 2002–2005 | 2 | mSHS | 0.97 | 54.9 | 47.9±12.2 | 500 (76.7) |
| Leiden EAC: ACPA-negative population | 273 | 1316 | 1993–2006 | 7 | mSHS | 0.91 | 100 | 58.9±16.3 | 187 (68.5) |
ACPA, anti-citrullinated protein autoantibodies; ICC, intraclass correlation coefficient; mSHS, van der Heijde-modified Sharp score.