Interreader intraclass correlation coefficients (ICC) and average status scores according to the RAMRIS in early arthritis patients (n = 441 in total) and patients with clinically suspect arthralgia (n = 82).
| Patient Population | Early Arthritis, n = 215, k = 2 | Early Arthritis, n = 226, k = 2 | Clinically Suspect Arthralgia, n = 82, k = 2 | Clinically Suspect Arthralgia, n = 40, k = 9 | |
|---|---|---|---|---|---|
| MTP joints | |||||
| BME | ICC (95% CI) | 0.91 (0.90–0.93) | 0.92 (0.90–0.94) | 0.77 (0.64–0.85) | 0.95 (0.93–0.97) |
| Median (IQR; max) | 0.5 (0–1.5; 20) | 0.5 (0–1.5; 18) | 0.0 (0–0.5; 6) | 0.1 (0.0–0.4; 5.4) | |
| Mean (SD) | 1.5 (2.6) | 1.1 (2.0) | 0.4 (0.9) | 0.4 (0.9) | |
| Synovitis | ICC (95% CI) | 0.90 (0.84–0.94) | 0.92 (0.88–0.94) | 0.92 (0.87–0.95) | 0.98 (0.97–0.99) |
| Median (IQR; max) | 1.0 (0–1.5; 8) | 0.5 (0–1.5; 10) | 0.0 (0–0.5; 6) | 0.2 (0.0–0.8; 6.2) | |
| Mean (SD) | 1.3 (1.7) | 1.2 (1.7) | 0.4 (0.9) | 0.5 (1.0) | |
| Tenosynovitis | ICC (95% CI) | 0.85 (0.78–0.90) | 0.80 (0.69–0.86) | 0.96 (0.93–0.97) | 0.99 (0.98–0.99) |
| Median (IQR; max) | 0.0 (0–1.5; 9) | 0.0 (0–1.5; 12) | 0.0 (0–0.0; 7.5) | 0.0 (0.0–0.1; 6.8) | |
| Mean (SD) | 1.1 (1.8) | 1.1 (1.9) | 0.2 (0.9) | 0.3 (1.1) | |
| Erosions | ICC (95% CI) | 0.88 (0.84–0.91) | 0.89 (0.86–0.92) | 0.87 (0.81–0.92) | 0.96 (0.93–0.97) |
| Median (IQR; max) | 0.5 (0–1.0; 9) | 0.0 (0–1.0; 7) | 0.0 (0–0.5; 2) | 0.0 (0.0–0.7; 1.4) | |
| Mean (SD) | 0.7 (1.0) | 0.6 (0.9) | 0.2 (0.5) | 0.3 (0.5) | |
| MCP joints | |||||
| BME | ICC (95% CI) | 0.60 (0.48–0.70) | 0.90 (0.82–0.93) | 0.78 (0.65–0.86) | 0.93 (0.89–0.96) |
| Median (IQR; max) | 0 (0–0.5; 7.5) | 0 (0–1; 14) | 0 (0–0; 2) | 0 (0–0; 0.9) | |
| Mean (SD) | 0.6 (1.3) | 1.0 (1.4) | 0.1 (0.4) | 0.1 (0.3) | |
| Synovitis | ICC (95% CI) | 0.91 (0.88–0.94) | 0.92 (0.89–0.94) | 0.91 (0.86–0.94) | 0.99 (0.98–0.99) |
| Median (IQR; max) | 0 (0–1; 6) | 0 (0–1; 9) | 0 (0–0; 5) | 0 (0–0; 4.9) | |
| Mean (SD) | 0.9 (1.5) | 0.8 (1.4) | 0.2 (0.6) | 0.2 (0.8) | |
| Tenosynovitis | ICC (95% CI) | 0.91 (0.88–0.93) | 0.91 (0.87–0.94) | 0.95 (0.92–0.97) | 0.98 (0.96–0.99) |
| Median (IQR; max) | 0 (0–2.5; 8.5) | 1.5 (0–3; 13) | 0 (0–1; 6) | 0.1 (0–1; 5.0) | |
| Mean (SD) | 1.5 (1.9) | 2.1 (2.4) | 0.8 (1.4) | 0.8 (1.3) | |
| Erosions | ICC (95% CI) | 0.93 (0.91–0.95) | 0.92 (0.90–0.94) | 0.93 (0.89–0.96) | 0.97 (0.95–0.98) |
| Median (IQR; max) | 0 (0–1; 5) | 0 (0–5; 5) | 0 (0–1; 4) | 0 (0–0.9; 1.9) | |
| Mean (SD) | 0.6 (1.0) | 0.7 (0.9) | 0.5 (0.9) | 0.4 (0.6) | |
| Wrist | |||||
| BME | ICC (95% CI) | 0.91 (0.88–0.93) | 0.93 (0.75–0.97) | 0.93 (0.90–0.96) | 0.96 (0.94–0.98) |
| Median (IQR; max) | 1 (0–2.5; 24) | 2 (0.5–4; 27) | 0.5 (0–1.5; 11) | 0.3 (0.1–1.2; 3.4) | |
| Mean (SD) | 2.2 (3.4) | 3.6 (4.8) | 1.1 (1.7) | 0.8 (1.0) | |
| Synovitis | ICC (95% CI) | 0.90 (0.87–0.92) | 0.93 (0.91–0.95) | 0.91 (0.87–0.94) | 0.96 (0.95–0.98) |
| Median (IQR; max) | 1 (0–3; 8) | 2 (0.5–3.5; 8) | 0.5 (0–1.5; 5.5) | 0.4 (0–1.1; 3.4) | |
| Mean (SD) | 1.8 (2.1) | 2.3 (2.1) | 0.9 (1.1) | 0.7 (0.9) | |
| Tenosynovitis | ICC (95% CI) | 0.93 (0.91–0.95) | 0.96 (0.95–0.97) | 0.97 (0.95–0.98) | 0.99 (0.98–0.99) |
| Median (IQR; max) | 1 (0–4; 11.5) | 1.5 (0–5; 13) | 0 (0–0; 10) | 0.1 (0–0.4; 9.2) | |
| Mean (SD) | 2.5 (3.0) | 2.8 (3.3) | 0.6 (1.7) | 0.8 (2.0) | |
| Erosions | ICC (95% CI) | 0.88 (0.84–0.91) | 0.94 (0.92–0.95) | 0.87 (0.79–0.92) | 0.96 (0.94–0.98) |
| Median (IQR; max) | 1.5 (0.5–3.5; 11) | 1.8 (0.5–3; 14) | 1 (0.5–2.5; 7.5) | 0.6 (0.2–2.3; 4.2) | |
| Mean (SD) | 2.2 (2.2) | 2.2 (2.2) | 1.5 (1.5) | 1.2 (1.2) |
Consecutive early arthritis patients were scored by 4 readers: the first 215 consecutive patients were scored by readers 1 and 2, the remaining 226 consecutive patients by readers 3 and 4. Eighty-two consecutive patients with clinically suspect arthralgia were scored by readers 5 and 6. Of these 82 patients, 40 were randomly selected and in addition also scored by 7 other readers. Results are based on a mean rating, absolute agreement, 2-way mixed effects model. RAMRIS: Rheumatoid Arthritis Magnetic Resonance Imaging Score; k: number of readers; MTP: metatarsophalangeal; MCP: metacarpophalangeal; BME: bone marrow edema; IQR: interquartile range.