Table 4. Spearman’s rank correlation coefficient and significant p values between FD values of skeleton, surface and general structure in both hemispheres and in whole brain WM with ALSFRS-R score (corrected for multiple comparisons using FDR p<0.007).

	Rho (r)	P value
Left Hemisphere WM
Skeleton	0.369	<0.001*
Surface	0.312	0.005*
General Structure	0.302	0.007
Right Hemisphere WM
Skeleton	0.365	<0.001*
Surface	0.360	<0.001*
General Structure	0.229	0.04
Whole brain WM
Skeleton	0.431	<0.001*
Surface	0.399	<0.001*
General Structure	0.369	0.001*

FD-fractal dimension, WM-white matter, FDR-false discovery rate, ALSFRS-R-ALS functional rate score-revised.

^*P<0.005 (false discovery rate corrected p value).