Dear Freesurfer experts,

 

I want to run a GLM to analyze the correlation between a continuous variable Y and a morphometric measure (eg. Cortical thickness). I want to control for some nuisance variables: sex, scan site, age, age squared, age * sex interaction, head size.

 

1. How should I go about formulating the FSDG file?
2. What should my design matrix be if I am only interested in the relationship between Y and the morphometric measure of interest after controlling for the various nuisance variables?

 

Thank you so much for the help!

 

Yours,

Sophia