Patient characteristics
| Leiden EAC | BARFOT | |
|---|---|---|
| Total number of patients | 678 | 715 |
| Total number of sets of radiographs | 3540 | 2483 |
| Maximum radiographic follow-up in years | 7 | 5 |
| Year of diagnosis | 1993–2006 | 1993–1999 |
| Female, n (%) | 459 (67.7) | 460 (64.3) |
| Age at diagnosis in years, mean (SD) | 56.6 (15.7) | 56.5 (15.2) |
| Autoantibodies | ||
| ACPA+/RF+, n (%) | 319 (47.1) | 357 (49.9) |
| ACPA+/RF−, n (%) | 45 (6.6) | 42 (5.9) |
| ACPA−/RF+, n (%) | 78 (11.5) | 74 (10.3) |
| ACPA−/RF−, n (%) | 236 (34.8) | 242 (33.8) |