Table VI.

Intraobserver reliability of Outerbridge classification for acetabular articular cartilage and femoral head chondral defects, and ALAD and Beck transition zone chondral injury rated by zone and the most severe rating noted

	Presence of cartilage defect			Rating of cartilage defect
Variable	AC1	Simple kappa	Proportion agreement	AC2	Weighted kappa	Weighted proportion agreement
Outerbridge classification of acetabular articular chondral defect
Zone A	0.926 (0.063)	−0.07 (0.042)	0.931 (0.058)	0.926 (0.063)	−0.07 (0.042)	0.931 (0.058)
Zone B	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Zone C	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Zone D	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Zone E	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Most severe	—	—	—	0.926 (0.063)	−0.070 (0.042)	0.931 (0.058)
Outerbridge classification of femoral chondral defect
Zone A (anterior)	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Zone B (superior)	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Zone C (anterior)	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Zone D (anterior)	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Zone E (anterior)	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Worst	—	—	—	N/A	N/A	1 (0)
ALAD classification of transition zone cartilage lesions
Zone A	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Zone B	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Zone C	N/A	N/A	1 (0.034)	0.545 (0.115)	0.313 (0.149)	0.805 (0.051)
Zone D	N/A	N/A	1 (0.034)	0.695 (0.083)	0.470 (0.130)	0.862 (0.043)
Zone E	N/A	N/A	1 (0.034)	N/A	N/A	1 (0.034)
Most severe	—	—	—	0.695 (0.083)	0.470 (0.130)	0.862 (0.043)
Beck classification of transition zone cartilage lesions
Transition zone A	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Transition zone B	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Transition zone C	0.890 (0.068)	−0.053 (0.031)	0.900 (0.056)	0.619 (0.120)	0.373 (0.160)	0.850 (0.043)
Transition zone D	N/A	N/A	1 (0)	0.647 (0.128)	0.532 (0.149)	0.844 (0.050)
Transition zone E	N/A	N/A	1 (0)	N/A	N/A	1 (0)
Most severe	—	—	—	0.679 (0.126)	0.566 (0.146)	0.856 (0.050)

Gwet’s AC and Fleiss’ kappa analysis. Agreement measures are shown as point estimate (standard error).