hi all.
I have 30 subjects in 3 group and would like to test group difference using TBSS with randomise
i tried two approaches.
In situation with A: 10, B: 10, C: 10 (three groups)
first try was
A B
1 0
1 0
0 1
0 1
0 1
for the design.mat of the first A and B groups with
1 -1 (A-B)
-1 1 (B-A)
for the design.con
and then repeated for groups B and C, then groups A and C
output was first_tfce_corrp_tstat1.nii.gz
second try was
A B C
1 0 0
1 0 0
0 1 0
0 1 0
0 1 0
0 0 1
0 0 1
0 0 1
0 0 1
for the design.mat of the 3 groups with
1 -1 0 (A-B)
-1 1 0 (B-A)
0 1 -1 (B-C)
0 -1 1 (C-B)
1 0 -1 (A-C)
-1 0 1 (C-A)
for the design.con (t-tests)
output was second_tfce_corrp_tstat1.nii.gz (contrast is 1 -1 0 ,first row)
But~!!!
the first and second results were different.
is it right? some mistake in design.con or design.mat ?
please reply me ~!! thanks all
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