ICC values [overall and mean (range) of all possible reader pairs] for SPARCC MRI SIJ SSS baseline scores for patients with SpA in 3 reading exercises. Mean ICC (range) = mean of ICC for all possible reader pairs with range of ICC scores.
| Exercise No. | Readers | Fat Metaplasia | Erosion | Backfill | Ankylosis | ||||
|---|---|---|---|---|---|---|---|---|---|
| Overall ICC | Mean ICC (range) | Overall ICC | Mean ICC (range) | Overall ICC | Mean ICC (range) | Overall ICC | Mean ICC (range) | ||
| Exercise 1, n = 45 | 4 | 0.78 | 0.73 (0.58–0.86) | 0.62 | 0.55 (0.45–0.77) | 0.66 | 0.63 (0.51–0.73) | 0.98 | 0.98 (0.96–0.99) |
| Exercise 2, n = 102 | 2 | 0.78 | — | 0.58 | — | 0.35 | — | 0.98 | — |
| Exercise 3, n = 40 | 3 | 0.71 | 0.71 (0.57–0.81) | 0.65 | 0.66 (0.60–0.71) | 0.66 | 0.64 (0.51–0.88) | 0.79 | 0.78 (0.72–0.87) |
ICC: intraclass correlation coefficient; SPARCC: the Spondyloarthritis Research Consortium of Canada; MRI: magnetic resonance imaging; SIJ: sacroiliac joint; SSS: Sacroiliac joint Structural Score; SpA: spondyloarthritis.