Longitudinal analysis (N=90): mean changes in scores after 6 and 12 months of follow-up, reliability analysis by intraclass coefficient of correlation, and responsiveness by the smallest detectable change
| Intrareader reliability | Inter-reader reliability | Responsiveness | |||||||
|---|---|---|---|---|---|---|---|---|---|
| ΔM0–M6 | ΔM0–M12 | ΔM0–M6 | ΔM0–M12 | M0–M12 | M0–M6 | ||||
| Variable | Reader | ICC (95% CI) | ICC (95% CI) | ICC (95% CI) | ICC (95% CI) | Mean Δ between readers (SD) | SDC | Mean Δ between readers (SD) | SDC |
| SCh bone | 1 | 0.73 (0.51 to 0.86) | 0.75 (0.53 to 0.87) | 0.63 (0.36 to 0.81) | 0.86 (0.72 to 0.93) | 9.3 (12.9) | 17.8 | 14.0 (16.9) | 23.5 |
| 2 | 0.99 (0.97 to 0.99) | 0.99 (0.99 to 0.99) | |||||||
| SCh plate | 1 | 0.91 (0.83 to 0.96) | 0.91 (0.83 to 0.95) | 0.87 (0.74 to 0.93) | 0.90 (0.81 to 0.95) | 10.3 (11.9) | 16.5 | 11.3 (15.5) | 21.5 |
| 2 | 0.99 (0.99 to 0.99) | 0.99 (0.99 to 0.99) | |||||||
| JT space | 1 | 0.88 (0.76 to 0.94) | 0.94 (0.88 to 0.97) | 0.83 (0.68 to 0.92) | 0.91 (0.81 to 0.96) | 13.7 (15.4) | 21.4 | 17.3 (21.0) | 29.1 |
| 2 | 0.99 (0.99 to 0.99) | 0.99 (0.99 to 0.99) | |||||||
| Total score | 1 | 0.85 (0.71 to 0.93) | 0.96 (0.91 to 0.98) | 0.86 (0.73 to 0.93) | 0.93 (0.86 to 0.97) | 26.0 (25.9) | 36.0 | 32.7 (34.3) | 47.6 |
| 2 | 0.99 (0.99 to 0.99) | 0.99 (0.99 to 1.00) | |||||||
Reader 1, GV; reader 2, RW.
M0: baseline; M6: month 6; M12: month 12; Δ: change in score; SDC = ±1.96 × SD Δ (change score)/(√2 × √k); k = 1, if not using average scores.
ICC, intraclass coefficient of correlation; JT, joint; SCh, subchondral; SDC, smallest detectable change.