Fig. 3. Bland-Altman plots.

Bland-Altman plots for CALIPR reproducibility subjects’ (A) brain MWF, (B) brain geometric mean of IET2, (C) spinal cord MWF, and (D) spinal cord IET2 ROI results from separate exams. Mean values from both exams are plotted on the x axis, and differences are plotted on the y axis. Solid lines indicate the mean bias (difference) of all data points [(A) +0.3%, (B) +0.3 ms, (C) +0.0%, and (D) +0.4 ms). Dotted lines indicate the positive (+1.96 SD) and negative (−1.96 SD) 95% limits of agreement. Brain ROIs include all WM, all gray matter (GM), and combined WM and GM from T₁w image segmentations, along with nine additional WM ROIs [all JHU WM labels combined: genu of corpus callosum (CC); splenium of CC; whole CC; posterior internal capsule; and frontal, occipital, parietal, and temporal lobes masked to WM] and four additional GM ROIs (cortical GM, caudate, thalamus, and putamen). Spinal cord ROIs include the whole cord, WM, GM, dorsal column, and lateral corticospinal tracts.