Observer effects
| Observer | Mean residual (SEM) | p value |
| 1 | 0.011 (0.038) | NS |
| 2 | −0.522 (0.076) | <0.0001 |
| 3 | −0.011 (0.045) | NS |
| 4 | −0.022 (0.040) | NS |
| 5 | −0.011 (0.052) | NS |
| 6 | 0.033 (0.042) | NS |
Mean residuals for each observer are relative to the “gold standard” KOSCHI score (calculated as the mean observers' scores excluding observer 2). KOSCHI scores have been treated as a continuous variable (1 to 8) for this analysis. Statistical significance of difference from zero by t test.