Table 4.

Intra-observer reliability for reading of MRI BLOKS features (weighted kappa)

BLOKS feature	Reliability (weighted kappa)
BML size	0.72
BML % area	0.67
% of lesion BML	0.79
Cartilage 1 morphology	0.95
Cartilage 2	0.93
Osteophyte	0.74
Synovitis	0.66
Effusion	0.77
Meniscal extrusion	0.95
Meniscus tear/cysts	0.99

BLOKS = Boston Leeds Osteoarthritis Knee Score

BML = Bone Marrow Lesion