Hi all,
I am doing a VBM analysis. I used GLM for a Single Group Average with Additional Covariate like this:
https://fsl.fmrib.ox.ac.uk/fsl/fslwiki/GLM#Single-Group_Average_with_Additional_Covariate
My contrast matrix is :
intercept variable age gender
0 1 0 0
I checked correlation of the interest variable with grey matter volume whilst controlling for age and gender and I found significant cluster after randomise.
However, when I looked at my behavioral results, I found big gender effect on my interest variable (female > male).
I wonder what is the correct contrast matrix to include this effect on my analysis. I know that (0 0 0 1) will show me the positive effect of gender on grey matter volume. But I guess it is not what I am looking.
Does it make sense to test (0 1 0 1) or (0 1 0 -1) for such effect?
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