dolphinede@aol.com wrote:
Dear freesurfer experts,
i am really a newbie in freesurfer.
I want to compare the thickness between different ages.
Is it correct to use gender as fixed factor, to look for its influence on thickness ?
Everything is a random factor in mri_glmfit/QDEC (which is also ok).
If i find no effects of gender on thickness i can put the factor gender out of the model ?
yes, but it probably won't change the result much. QDEC will automatically add an intercept.
Otherwise if there will be effects of gender on thickness it remains in the model. So that the effect of age on thickness
can be questioned like this:
Does the correlation between thickness and age, accounting for gender, differ from zero?
Yes. doug
Best regards
Daniel
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