Table 4 Intra- and interobserver kappa coefficients (95% confidence interval) and interobserver absolute agreement (%) for CBCT imaging features describing anatomy and deformity in a sample of 84 children with JIA, right TMJ. Cohen's linear weighted kappa coefficients unless specified. Grading outlined in Table 2

Overall impression of TMJ deformity (0–2)

0.81 (0.69–0.92)^a

0.70 (0.61–0.79)^b

64/82 (78%)

Flattening of the articular eminence and glenoid fossa (0–2)

0.77 (0.66–0.89)

0.65 (0.51–0.79)

62/82 (76%)

Surface irregularity of the articular eminence and glenoid fossa (0–2)

0.66 (0.48–0.84)

0.55 (0.32–0.79)

70/79 (88%)

Continuity of the articular eminence and glenoid fossa surface (0–2)

0.46 (0.09–0.82)^a

0.43 (0.30–0.56)^b

67/76 (88%)

Flattening of the condyle—sagittal view (0–3)

0.82 (0.75–0.90)

0.76 (0.67–0.85)

59/83 (71%)

Flattening of the condyle—coronal view (0–2)

0.71 (0.58–0.83)

0.60 (0.46–0.74)

60/84 (71%)

Reduced condylar volume (0–4)

0.58 (0.43–0.73)^a

0.47 (0.38–0.56)^b

50/83 (60%)

Surface irregularity of the condyle (0–2)

0.77 (0.66–0.89)

0.70 (0.57–0.83)

65/82 (79%)

Continuity of the condylar surface (0–1)

0.66 (0.46–0.85)^a

0.51 (0.38–0.63)^b

55/77 (71%)

Position of the condyle in the glenoid fossa (0–6)

0.38 (0.18–0.58)^a

0.10 (0.02–0.18)^b

32/83 (39%)

Subchondral sclerosis in the articular eminence and glenoid fossa (0–2)

0.65 (0.52–0.78)

0.60 (0.47–0.73)

51/79 (65%)

Osteophyte of the articular eminence and glenoid fossa (0–1)

0.64 (0.31–0.97)^a

0.46 (0.09–0.83)^a

73/79 (92%)

Subchondral sclerosis of the condyle (0–2)

0.78 (0.64–0.92)

0.63 (0.46–0.81)

70/82 (85%)

Osteophyte of the condyle (0–1)

0.65 (0.28–1.00)^a

0.37 (0.10–0.64)^a

71/82 (85%)