Hi,
I am trying to apply VBM and TBSS on a group of multiple sclerosis patients
and the matching control subjects and also trying to see the effect of age and
disease duration.
When creating the design for randomise with Glm, I add one EV with the
demeaned values for the patients' disease duration and zeros for control
subjects. For the age, I add 2 EVs one for the patients and the other for the
controls and demean each separately.
My first question is whether what I’m doing until now is correct or not?
After, for the contrast selection, if I want to study the age effect or the
disease duration I use the following:
C1 patients>control 1 -1 0 0
C2 control>patients -1 1 0 0
My second question is whether the contrasts are right or no?
Thank you for your help
Sincerely
Salem
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