Dear FSL experts,
I searched the FSL archive but it is still kind of confusing to me about the
demean option.
I have two groups (control vs patient) and I would like to see the difference
between their FA value in TBSS analysis while controlling for the nuisance
covarietes (age).
Could anyone tell me if my design matrix is correct and if I need to add -D
option in randomise.
deisgn matrix:
EV1 EV2 EV3 EV4
1 0 -2 0
1 0 -2 0
1 0 4 0
0 1 0 -1
0 1 0 2
0 1 0 -1
EV3 is the demeaned age for control group which I padded with zeros. EV4 is
hte demeaned age for patient group, which I also padded with zeros.
design contrast:
1 -1 (Control >Patient)
-1 1 (patient > control)
Then I run: randomise -i all_FA_skeleton -o tbss -m mean_FA_skeleton_mask -
d design.mat -t design.con -n 5000 -c 3 -D
My question is, do I have to run randomise with the -D option in this case?
I appreciate any input you might have. Thank you so much.
Yi-Shin
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