[Freesurfer] Questions about fsgd file & contrast

Dear list,

We have a question about the set up of the FSGD file.

We have 1 group, 2 continued covariates (age & mintues), 1 discontinued covariate (sex)

GroupDescriptorFile 1 Title G1V3 Class Main Variables Age Sex Minutes Input subject1 Main 30 0 1200 Input subject2 Main 40 1 180

My question is

1) How to enter the column "sex" in FSGD. Can I input 1 for Male and 0 for Female?

2) What would be the Main Contrast (regress out effect of sex & age)?

(Null Hypothesis: the intercept/offset is different than 0 after regressing out the effects of age and sex)

3) If I want to correlate the continued variable (minutes) with the Thickness, is it correct in this way ? :

0 0 0 1

Thanks so much

Jahanvi