Characteristics of patients in discovery and validation cohorts
| Variable | Discovery total | Discovery cohort 1 | Discovery cohort 2 | Discovery cohort 3 | Discovery cohort 4 | Validation |
| No of patients (after QC) | 113 (106) | 12 (11) | 20 (17) | 11 (10) | 70 (68) | 60 (60) |
| Osteoarthritis joint | Knee or hip | Knee | Knee | Hip | Knee | Knee |
| Low-grade OA cartilage samples after QC | 87 | 11 | 16 | 10 | 50 | 60 |
| High-grade OA cartilage samples after QC | 95 | 10 | 16 | 10 | 59 | – |
| Synovium samples after QC | 77 | – | 16 | – | 61 | – |
| Females, n (%) after QC | 63 (59) | 2 (19) | 12 (71) | 8 (73) | 41 (60) | 27 (45) |
| Age, average years (range) after QC | 69 (38–88) | 69 (50–88) | 70 (54–79) | 61 (44–88) | 70 (38–84) | 72 (63–85) |
OA, osteoarthritis; QC, quality control.