Dear Conn users, dear Alfonso,

I am currently analysing rs-fMRI from 3 different sites (scan from different manufacturers but all with exactly the same scan parameters). I have some troubles to correct for the site effect by using conn.
I have read the post suggesting that GCOR could be used when comparing subjects across different sites and I have some questions :

1) Is there any other way to correct the site effect by using categorical 2nd level covariates ?

2) If I use GCOR, should I just add this covariate in the denoising step ? Is there any reference that can be cited to justify this method ?

Many thanks in advance for your help,

Best wishes,

Ali