Arthroscopy vs. MRI for a detailed assessment of cartilage disease in osteoarthritis: diagnostic value of MRI in clinical practice

Table 1 Weighted kappa values and 95% confidence intervals for inter- and intra-observer agreement of MRI for the three compartments of the knee joint.

	weighted kappa values and 95% confidence intervals^†
	patellofemoral compartment	medial compartment	lateral compartment	all compartments
reader 1 vs. reader 2	0.51 (0.37-0.65)	0.59 (0.47-0.71)	0.75 (0.64-0.85)	0.65 (0.58-0.72)
AC vs. reader 1	0.52 (0.37-0.66)	0.62 (0.48-0.75)	0.65 (0.54-0.76)	0.62 (0.55-0.69)
AC vs. reader 2	0.32 (0.17-0.47)	0.49 (0.35-0.62)	0.57 (0.44-0.70)	0.50 (0.42-0.58)

* AC = arthroscopic findings
^† < 0.20 = poor, 0.21-0.40 = fair, 0.41-60 = moderate, 0.61-0.80 = good, 0.81-1.0 = very good