Table 1.

Status scores, progression scores, ICCs and SDCs of facet joints

	Reader 1	Reader 2	ICC (95% CI)	SDC
	Mean (s.d.) range	Mean (s.d.) range
Whole spinea max score 38
Baseline	7.3 (10) 0–34	9.4 (10.9) 0–37	0.93 (0.87, 0.96)
Follow-up	7.8 (9.7) 0–34	10.3 (10.9) 0–34	0.91 (0.82, 0.95)
Progression score	1.0 (2.8) −8.4–11.9	1.1 (2.6) −4.2–11.2	0.56 (0.22, 0.75)	1.98
Cervical segmentb max score 6
Baseline	0.9 (1.8) 0–6	1.1 (2) 0–6	0.84 (0.73, 0.90)
Follow-up	0.7 (1.6) 0–6	1.2 (1.9) 0–6	0.72 (0.52, 0.84)
Progression score	0.0 (0.4) −2–1	0.0 (0.4) −2–1	0.91 (0.83, 0.95)	0.22
Thoracic segmentc max score 22
Baseline	5.4 (7.4) 0–22	6.5 (7.6) 0–22	0.91 (0.85, 0.95)
Follow-up	6.0 (7.2) 0–22	7.3 (7.9) 0–22	0.90 (0.82, 0.94)
Progression score	0.9 (2.5) −8.8–7	0.9 (2.3) −4.4–11	0.56 (0.21, 0.75)	2.67
Lumbar segment max score 10
Baseline	1.0 (2.5) 0–10	1.8 (3.1) 0–10	0.81 (0.67, 0.89)
Follow-up	1.1 (2.5) 0–10	1.8 (3.0) 0–10	0.85 (0.73, 0.92)
Progression score	0.0 (0.8) −2–3	0.2 (0.9) −2–5	0.10 (−0.58, 0.48)	1.14

^aJoint levels C2–C5 and T2–S1.

^bJoint levels C2–C5.

^cJoint levels T2–L1.

Baseline: n = 60. Follow-up: n = 52 (r1), n = 53 (r2). Whole spine progression score: n = 50 (r1), n = 52 (r2), n = 50 (ICC, SDC). Cervical progression score: n = 44 (r1), n = 45 (r2), n = 40 (ICC, SDC). Thoracic progression score: n = 50 (r1), n = 52 (r2), n = 50 (ICC, SDC). Lumbar progression score: n = 51 (r1), n = 52 (r2), n = 51 (ICC, SDC).

ICC: intraclass correlation coefficients; SDC: smallest detectable change.