Table 6 Longitudinal (M0–M36) intraobserver reproducibility and sensitivity to change of joint space width measurements
View | Observer | JSW change (mm; mean ± SD) | Difference (mm; mean ± SD) | 95% CI approximation of bias | Limits of agreements | ICC value (95% CI) | SRM calculated on reading 1 (95% CI) | |
|---|---|---|---|---|---|---|---|---|
Reading 1 | Reading 2 | |||||||
Pelvic | 1 | -0.40 ± 0.65 | -0.49 ± 0.54 | 0.09 ± 0.36 | -0.01 to +0.19 | -0.63 to +0.81 | 0.81 (0.69–0.89) | -0.61 (-0.65 to -0.57) |
2 | -0.54 ± 0.66 | -0.49 ± 0.67 | -0.05 ± 0.16 | -0.09 to -0.01 | -0.37 to +0.27 | 0.97 (0.95–0.98) | -0.82 (-0.84 to -0.80) | |
Mean (1 + 2) | -0.47 ± 0.62 | -0.49 ± 0.57 | 0.02 ± 0.18 | -0.2 to +0.06 | -0.34 to +0.38 | 0.95 (0.92–0.97) | -0.76 (-0.77 to -0.73) | |
Hip AP | 1 | -0.39 ± 0.61 | -0.46 ± 0.59 | 0.07 ± 0.30 | -0.01 to +0.15 | -0.53 to +0.67 | 0.87 (0.78–0.92) | -0.64 (-0.67 to -0.61) |
2 | -0.49 ± 0.66 | -0.49 ± 0.66 | -0.00 ± 0.14 | -0.04 to +0.04 | -0.28 to +0.28 | 0.97 (0.96–0.99) | -0.75 (-0.77 to -0.73) | |
Mean (1 + 2) | -0.44 ± 0.62 | -0.48 ± 0.60 | 0.03 ± 0.16 | -0.01 to +0.07 | -0.29 to +0.35 | 0.96 (0.94–0.98) | -0.72 (-0.74 to -0.70) | |
Oblique | 1 | -0.46 ± 0.59 | -0.37 ± 0.50 | -0.09 ± 0.40 | -0.21 to +0.03 | -0.89 to +0.71 | 0.73 (0.57–0.84) | -0.77 (-0.80 to -0.74) |
2 | -0.47 ± 0.67 | -0.52 ± 0.64 | 0.05 ± 0.23 | -0.10 to +0.11 | -0.41 to +0.51 | 0.93 (0.88–0.96) | -0.70 (-0.74 to -0.67) | |
Mean (1 + 2) | -0.46 ± 0.61 | -0.45 ± 0.53 | 0.03 ± 0.16 | -0.10 to +0.07 | -0.29 to +0.35 | 0.91 (0.85–0.95) | -0.76 (-0.79 to -0.73) | |