Dear guys,
I was doing group analysis (command-line) on two groups (patients and control, no age or other information). The data has been "qcached", and after following the three steps as "mris_preproc, mri_glmfit and mri_glmfit-sim" shown in the tutorial on the Freesurfer website, I obtained the difference on thickness in both left and right hemispheres, which seems great. However, when I repeated the above steps on other measures, e.g. area, area.pial, volume (also replaced the parts of "thickness" in the command lines), the results seemed to be exactly the same again as those in the thickness comparison, even the p-value numbers in the file "cache.th40.neg.sig.cluster.summary" were the same. I was using Freesurfer v6.0-beta, and I performed the individual data analysis on a linux cluster and I copied/downloaded the whole "qcached" subject directory to my linux laptop to perform the group comparison, both using the same version of Freesurfer, does it matter? Or do you know why it happened like this?
Thanks, Kaiming