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Table 3 Validity

From: Validity and reliability of using photography for measuring knee range of motion: a methodological study

  Mean XRay Mean Rater Mean Difference
(95% CI)
Diff. p-value
(2-sided)
Concordance Correlation
Coefficient (95% CI)
B-A Mean Difference
(95% Limits of Agreement)
Marker Method
Flexion (degrees) - XRay > 20
XRay v RF 90.9 91.5 0.6 (-1.3 to 2.4) 0.54 0.981 (0.970 to 0.993) 1.2 (-7.6 to 10.0)
XRay v PT 90.9 90.1 -0.8 (-3.0 to 1.3) 0.42 0.975 (0.960 to 0.991) -0.4 (-7.1 to 6.4)
XRay v OS 90.9 90.8 -0.1 (-2.1 to 1.9) 0.93 0.980 (0.966 to 0.993) 1.5 (-6.1 to 9.1)
Extension (degrees) - XRay <= 20
XRay v RF 6.0 13.8 7.8 (2.2 to 13.5) 0.01 0.540 (0.359 to 0.721) 9 (-6.0 to 24.0)
XRay v PT 6.0 12.1 6.1 (1.2 to 11.0) 0.02 0.611 (0.430 to 0.792) 3 (-9.3 to 15.6)
XRay v OS 6.0 12.8 6.8 (1.9 to 11.7) 0.01 0.586 (0.404 to 0.767) 8 (-9.0 to 25.0)
Line of Femur Method
Flexion (degrees) - XRay > 20
XRay v RF 90.9 92.1 1.2 (-0.8 to 3.2) 0.21 0.978 (0.963 to 0.994) 1.0 (-6.0 to 8.1)
XRay v PT 90.9 90.5 -0.4 (-1.9 to 1.2) 0.62 0.988 (0.980 to 0.996) -0.8 (-10.2 to 8.5)
XRay v OS 90.9 92.4 1.5 (-0.2 to 3.2) 0.08 0.982 (0.971 to 0.994) -0.1 (-8.9 to 8.7)
Extension (degrees) - XRay <= 20
XRay v RF 6.0 15.0 9.0 (3.1 to 14.9) <0.01 0.478 (0.294 to 0.662) 8.9 (-6.7 to 24.6)
XRay v PT 6.0 9.1 3.1 (-1.8 to 8.0) 0.18 0.678 (0.493 to 0.862) 6.1 (-6.5 to 18.7)
XRay v OS 6.0 14.0 8.0 (1.3 to 14.7) 0.02 0.497 (0.305 to 0.689) 6.8 (-5.8 to 19.3)
  1. RF = research fellow; PT = physiotherapist; OS = orthopaedic surgeon; v = versus; B-A = Bland-Altman