Descriptive baseline characteristics of the study knees in primary and secondary analyses. Values are n (%).
| Characteristics | Full OAI Cohort, n = 8870 knees | Bilateral ROA, n = 2694 knees | No ROA, n = 2408 knees | Unilateral ROA, n = 653 knees |
|---|---|---|---|---|
| Females | 5182 (58.4) | 1676 (62.2) | 1346 (55.9) | 320 (49.0) |
| Chronic knee symptoms* | 3221 (36.3) | 1264 (46.9) | 639 (26.6) | 146 (22.4) |
| WOMAC knee pain score ≥ 3* | 2916 (32.9) | 1221 (45.3) | 512 (21.3) | 120 (18.4) |
↵* Frequent and WOMAC knee pain are reported for both knees within a participant for the full OAI cohort and among those with bilateral ROA or no ROA because both knees could contribute an outcome. Frequent and WOMAC knee pain are reported for the knee without ROA. OAI: Osteoarthritis Initiative; ROA: radiographic osteoarthritis (Kellgren-Lawrence grade ≥ 2); WOMAC: Western Ontario and McMaster Universities Osteoarthritis Index.