MRI field strength was 1.5 T in 16 studies, 2.0 T in 1 study, and 3.0 T in 2 studies. Tissue segmentation on MR images was semi-automated in 9 studies and fully automated in 10 studies. WM volume was adjusted for ICV in 11 studies, with the remaining 8 studies reporting either raw volume or Z-score or percent difference with respect to the comparison group.
