Outcomes of the conservative hip preservation treatment in patients with osteonecrosis of the femoral head: With 4-year follow-up

Table 3 Kappa consistency coefficients for radiological data at the final follow-up

Items	Intra-observer kappa		Inter-observer
	Observer 1	Observer 2	Kappa	P value
AROC stage	0.942	0.454	0.504	< 0.001
JIC classification	0.928	0.374	0.348	< 0.001
Lesion size	0.959	0.492	0.430	< 0.001
Collapse degree	0.895	0.638	0.666	< 0.001

ARCO: Association Research Circulation Osseous; JIC: Japanese Investigation Committee.