Hi FSL experts!
I have seen some questions in the archive related with this, but I'm pretty new with this kind of analysis so just wanted to be sure about them.
I'm running a TBSS analysis trying to find differences between a control (EV1) and a patient (EV2) group. Till now, I have found statistical differences in FA and also in AD, RD and MD with age (EV3), gender (EV4), and ICV (EV5) as covariates (all of them demeaned).
My next step is to analyze if there are any differences in terms of psychological values and here are my doubts…
- First I want to test the correlation between FA and these data, so EV6=psychological values (demeaned?) and contrast matrix should be:
0 0 0 0 0 1
0 0 0 0 0 -1
right? should I add an intercept?
- Does it give you information about differences between groups? I'm not sure about the difference between this contrast design and this one (EV6=psychological values for controls; EV7=psychological values for patients):
0 0 0 0 0 1 0
0 0 0 0 0 -1 0
0 0 0 0 0 0 1
0 0 0 0 0 0 -1
Sorry for the mess, but I'm a bit lost.
Thank you so much in advance.
Best,
Marta
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