Distribution of SPARCC MR scores, the intra- and interreader reliability assessed by ICC, and responsiveness of scores before and after biologic or nonbiologic treatments, indicated by standardized response mean (SRM).
| Variables | SPARCC Total Score | SPARCC Scoring System Indices | ||
|---|---|---|---|---|
| Bone Marrow Edema | Intensity (Intense Edema) | Extent (Extensive Edema) | ||
| Average score in all baseline examinations (± SD) | 9.2 (12.1) | 7.6 (9.6) | 0.6 (1.2) | 1.0 (1.8) |
| Median score in all baseline examinations (IQR) | 2 (0–19) | 2 (0–16) | 0 (0–1) | 0 (0–2) |
| Average score in baseline examinations showing sacroiliitis (± SD) | 17.8 (11.4) | 14.7 (8.7) | 1.2 (1.4) | 1.9 (2.1) |
| Median score in baseline examinations showing sacroiliitis (IQR) | 19 (6–24.5) | 16 (6–20) | 1 (0–2) | 2 (0–2.5) |
| SPARCC intrareader reliability (n = 90 examinations) | ICC (95% CI) | |||
| Reader 1 | 0.99 (0.98–0.99) | 1 | 0.79 (0.70–0.86) | 0.95 (0.93–0.97) |
| Reader 2 | 1 | 1 | 0.85 (0.78–0.90) | 0.97 (0.95–0.98) |
| SPARCC interreader reliability | 0.99 (0.98–0.99) | 1 | 0.87 (0.81–0.91) | 0.98 (0.97–0.99) |
| SPARCC responsiveness (n = 17, 18 examination pairs) | SRM in biologic and nonbiologic treatments | |||
| Reader 1 first read | 0.591, 0.633 | 0.630, 0.634 | 0.270, 0.413 | 0.429, 0.441 |
| Reader 2 second read | 0.560, 0.657 | 0.597, 0.648 | 0.236, 0.517 | 0.307, 0.453 |
| Reader 2 first read | 0.602, 0.647 | 0.626, 0.657 | 0.397, 0.473 | 0.443, 0.441 |
| Reader 1 second read | 0.529, 0.674 | 0.569, 0.667 | 0.275, 0.488 | 0.322, 0.528 |
| Pooled average of 4 readings | 0.582, 0.667 | 0.619, 0.666 | 0.302, 0.481 | 0.384, 0.476 |
| Change score reliability (ICC) | 0.99, 0.97 | 1.00, 0.98 | 0.65, 0.81 | 0.92, 0.95 |
Presence of sacroiliitis was defined as SPARCC score of ≥ 2. SPARCC: Spondyloarthritis Research Consortium of Canada; MR: magnetic resonance; ICC: intraclass correlation coefficients; IQR: interquartile range.