Timepoint | Reader 1 | Reader 2 | ICC (95% CI) | |
Whole spine (max score 552) | ||||
Baseline | Mean (SD) Median (range) | 163 (126) 127 (11–428) | 158 (124) 115 (5–445) | 0.99 (0.98 to 0.99) |
2 years | Mean (SD) Median (range) | 180 (130) 157 (14–455) | 175 (130) 125 (7–459) | 0.99 (0.98 to 0.99) |
Change score | Mean (SD) Median (range) | 16 (21) 10 (−11 to 96) | 17 (21) 10 (−6 to 106) | 0.77 (0.63 to 0.86) |
Cervical spine (max score 144) | ||||
Baseline | Mean (SD) Median (range) | 30 (41) 8 (0–140) | 28 (37) 8 (0–134) | 0.98 (0.96 to 0.99) |
2 years | Mean (SD) Median (range) | 32 (42) 12 (0–140) | 32 (40) 10 (0–135) | 0.95 (0.92 to 0.97) |
Change score | Mean (SD) Median (range) | 2 (7) 0 (−12 to 39) | 4 (8) 0 (−9 to 39) | 0.57 (0.35 to 0.73) |
Thoracic spine (max score 264) | ||||
Baseline | Mean (SD) Median (range) | 97 (77) 77 (1–253) | 95 (77) 72 (0–264) | 0.98 (0.96 to 0.99) |
2 years | Mean (SD) Median (range) | 109 (80) 85 (1–256) | 106 (81) 78 (0–264) | 0.99 (0.98 to 0.99) |
Change score | Mean (SD) Median (range) | 12 (18) 6 (−6 to 97) | 10 (18) 6 (−12 to 93) | 0.75 (0.60 to 0.85) |
Lumbar spine (max score 144) | ||||
Baseline | Mean (SD) Median (range) | 36 (36) 24 (0–140) | 35 (35) 22 (0–140) | 0.97 (0.95 to 0.98) |
2 years | Mean (SD) Median (range) | 39 (38) 26 (0–144) | 38 (36) 29 (0–144) | 0.96 (0.93 to 0.98) |
Change score | Mean (SD) Median (range) | 3 (4) 2 (−7 to 13) | 3 (4) 1 (−5 to 15) | 0.32 (0.04 to 0.55) |
ICC, intraclass correlation coefficient.