Histograms of the relative number of white matter voxels at different values of COH, COU, average OVL, average DTED, DVED and LETD, and TVDT, for registration of Group 1 (A) and Group 2 (B) data to ICBM81 (light grey curve), IIT2 (dark grey curve) and study-specific (SS, black curve) templates using the preferred registration method for each case.