Skip to main content

Advertisement

Table 7 Intra-observer agreements for MRI changes in the SIJ and global assessment

From: Spondyloarthritis-related and degenerative MRI changes in the axial skeleton - an inter- and intra-observer agreement study

MRI changes Observers Observed agreement (%) Expected agreement (%) Weighted Kappa (95% CI) Number of SIJ regions
BMO AA 99.57 89.42 .96 (.92–.98) 384
BB 98.99 89.19 .91 (.85–.95) 384
  Intensity of BMO 1 AA 92.42 67.36 .77 (.58–.96) 66
BB 95.95 83.97 .75 (.47–1.00) 74
  Depth of BMO 1 AA 95.45 51.93 .91 (.80–1.00) 66
BB 91.89 55.84 .82 (.68–.96) 74
FMD AA 99.33 85.49 .95 (.92–.97) 384
BB 98.06 82.15 .89 (.84–.93) 384
  Depth of FMD 1 AA 95.57 52.40 .80 (.64–.97) 53
BB 87.88 52.25 .75 (.58–.91) 66
Erosions AA 98.61 93.52 .79 (.60–.92) 348
BB 99.02 91.96 .88 (.80–.93) 384
Subchondral sclerosis AA 99.62 96.84 .88 (.71–.96) 384
BB 99.62 96.48 .89 (.77–.95) 384
Ankylosis AA - - - -
BB 99.54 97.26 .83 (.52–.95) 384
Global assessment2 AA 98.37 84.61 .89 (.82–.95) 463
  BB 95.79 80.20 .79 (.52–.93) 463
  1. SIJ: sacroiliac joints, BMO: Bone marrow oedema, FMD: fatty marrow deposition, - Too few positive ratings for one of the observers to be included in the analysis 1Only observations where the reader on both the readings agreed on the presence of BMO/FMD were kept in the analysis. 2Assessed on the entire MRI scan, not only the SIJ. 3Number of patients assessed.