Table 4.
Intra- and inter-observer reliability of segmenting WMLs using MCMxxxVI and FLAIR-derived thresholds
| Measurements (voxels) | For the same analyst | For two analysts | ||||
|---|---|---|---|---|---|---|
| Mean ± SD | Min. | Max. | Mean ± SD | Min. | Max. | |
| FLAIR-derived threshold: differences between two WML volume measurements using the same threshold | 759.00 ± 733.53 | 17 | 2,628 | – | – | – |
| FLAIR-derived threshold: differences between two WML volume measurements using a different threshold for each measurement | 310.00 ± 9,923.98 | 3,664 | 16,444 | – | – | – |
| MCMxxxVI: differences between two WML volume measurements | 69.00 ± 326.08 | 1 | 698 | 761.00 ± 822.21 | 3 | 1,881 |
Same threshold indicates that the same threshold was applied to the subject each time. Different threshold indicates that an individual threshold was derived for that subject each time the WML volume was measured (which is a closer reflection of the usual practice)