Table 4 Inter-observer agreements for spinal MRI changes
| Â | Observers | Observed agreement (%) | Expected agreement (%) | Pairwise weighted Kappa (95% CI) | Number of levels1 |
|---|---|---|---|---|---|
Type of signal change | AB | 95.70 | 88.65 | .62 (.56–.68) | 2208 |
AC | 96.38 | 91.13 | .59 (.51–.66) | 2208 | |
BC | 95.70 | 89.73 | .58 (.51–.65) | 2208 | |
Combined |  |  | .60 (.55–.65) | 2208 | |
  Signal change in the corner 2 | AB | 83.51 | 56.32 | .62 (.46–.79) | 97 |
AC | 80.00 | 61.22 | .48 (.28–.69) | 70 | |
BC | 72.15 | 64.01 | .23 (.00–.46) | 79 | |
Combined3 |  |  | .53 (.42–.64) | 114 | |
  Location of signal change 2 | AB | 92.78 | 42.56 | .87 (.78–.95) | 97 |
AC | 97.14 | 45.31 | .95 (.86–1.00) | 70 | |
BC | 94.94 | 46.37 | .91 (.79–.98) | 79 | |
Combined |  |  | .90 (.83–.96) | 66 | |
  Size of signal change 2 | AB | 91.49 | 75.74 | .65 (.45–.80) | 97 |
AC | 93.57 | 74.92 | .74 (.54–.89) | 70 | |
BC | 97.61 | 90.05 | .76 (.64–.86) | 79 | |
Combined3 |  |  | .66 (.58–.75) | 114 | |
Total size of BMO in the DVU | AB | 99.41 | 98.71 | .54 (.32–.74) | 1104 |
AC | 99.23 | 99.07 | .16 (.06–.33) | 1104 | |
BC | 99.62 | 99.40 | .43 (.24–.63) | 1104 | |
Combined3 |  |  | .38 (.34–.41) | 1104 | |
Total size of FMD in the DVU | AB | 99.09 | 98.12 | .52 (.36–.66) | 1104 |
AC | 99.25 | 98.27 | .57 (.41–.72) | 1104 | |
BC | 99.12 | 98.31 | .47 (.32–.63) | 1104 | |
Combined3 |  |  | .52 (.49–.56) | 1104 | |
Total size of mixed lesions in the DVU | AB | 99.39 | 98.99 | .39 (.12–.65) | 1104 |
AC | 99.50 | 99.42 | .13 (.00–.36) | 1104 | |
BC | 99.59 | 99.19 | .49 (.22–.74) | 1104 | |
Combined3 |  |  | .36 (.32–.40) | 1104 | |
Erosions | AB | - | - | - | - |
AC | - | - | - | - | |
BC | 99.83 | 99.72 | .40 (.17–.56) | 2208 | |
Combined3 | Â | Â | Â | - | |
Syndesmophytes or vertebral fusion | AB | 99.71 | 99.17 | .65 (0.00–.91) | 1104 |
AC | - | - | - | - | |
BC | - | - | - | - | |
Combined3 | Â | Â | - | - | |
BMO at the apophyseal joint | AB | - | - | - | - |
AC | 99.55 | 98.83 | .61 (.30–.93) | 1104 | |
BC | - | - | - | - | |
Combined3 | Â | Â | - | - | |
Disc degeneration | AB | 98.61 | 94.73 | .74 (.67–.79) | 1104 |
AC | 98.91 | 94.98 | .78 (.72– .84) | 1104 | |
BC | 98.97 | 95.61 | .77 (.70–.82) | 1104 | |
Combined3 |  |  | .76 (.74–.78) | 1104 | |
Disc contour | AB | 98.55 | 95.17 | .70 (.63–.76) | 1104 |
AC | 98.44 | 94.29 | .73 (.65–.79) | 1104 | |
BC | 97.36 | 91.96 | .67 (.60–.74) | 1104 | |
Combined3 |  |  | .70 (.68–.73) | 1104 | |
Herniation in the vertebral endplate | AB | 98.73 | 96.27 | .66 (.49–.83) | 1104 |
AC | 98.10 | 97.40 | .27 (.06–.48) | 1104 | |
BC | 98.28 | 97.75 | .23 (.01–.46) | 1104 | |
Combined3 |  |  | .43 (.40–.47) | 1104 | |
Scheurmann’s changes | AB | 98.46 | 98.47 | -.01 (-.01–0.00) | 1104 |
AC | 98.92 | 97.58 | .14 (-.05–.32) | 1104 | |
BC | 98.55 | 98.20 | .20 (-.04–.43) | 1104 | |
|  | Combined3 |  |  | .12 (.08–.15) | 1104 |