Table 2.

Intra-class correlation coefficients (ICC) for measurement of relative percentage of extrusion (RPE) and shrinkage

	Months	Inter-observer ICC	Intra-observer ICC
RPEaa	3	0.897 (0.806–0.946)	0.928 (0.897–0.952)
	12	0.871 (0.758–0.936)	0.947 (0.934–0.959)
RPEpb	3	0.900 (0.812–0.950)	0.917 (0.895–0.924)
	12	0.863 (0.740–0.933)	0.888 (0.796–0.902)
RPErc	3	0.954 (0.914–0.977)	0.966 (0.953–0.978)
	12	0.921 (0.851–0.962)	0.918 (0.897–0.926)
Shrinkage	3	0.935 (0.878–0.968)	0.976 (0.966–0.990)
	12	0.914 (0.839–0.957)	0.944 (0.929–0.955)

Values are expressed as ICC and 95% CI in parentheses

^aRPEa relative percentage of extrusion at anterior meniscus

^bRPEp relative percentage of extrusion at posterior meniscus

^cRPEr relative percentage of extrusion at radial meniscus