Table 2.

Agreement between radiographic and clinical knee OA, and radiographic and self-reported knee OA

	Clinical knee OA		Self-reported OA
	OA positive	OA negative	OA positive	OA negative
Radiographic OA
OA Positive	39	120	52	107
OA Negative	20	216	20	216
Sensitivity	24.5%		32.7%
Specificity	91.5%		91.5%
Positive Predictive Value	66.1%		72.2%
Negative Predictive Value	64.3%		66.9%
Relative Risk (95% CI)	1.85 (1.47 – 2.33)		2.18 (1.77 – 2.69)