Hello,

It is not advisable to mix versions of FreeSurfer as results across different versions of FreeSurfer are expected to differ, even if by a little. We recommend that the same version of FreeSurfer be used to process every case in your dataset. If you were to proceed with an analysis of, for example, a cohort processed with 5.3 versus 6.0, differences in stats could be partially due to difference in version.

Cheers, Bill

From: freesurfer-bounces@nmr.mgh.harvard.edu on behalf of Stephanie K rklinden@gmail.com Reply-To: Freesurfer support list freesurfer@nmr.mgh.harvard.edu Date: Wednesday, November 4, 2020 at 3:00 PM To: "freesurfer@nmr.mgh.harvard.edu" freesurfer@nmr.mgh.harvard.edu Subject: Re: [Freesurfer] Meta-analysing brain measure statistics across multiple cohorts using different versions of Freesurfer

External Email - Use Caution Hi,

I am planning on meta-analysing the effects of regional and global cortical thickness + surface area, as well as subcortical volumes of 3 cohorts. Two of them have been processed using Freesurfer 5.3 and one one of them has been Freesurfer 6.0. Is it wrong to meta-analyse them due to differences in the pipeline? I would really appreciate your advice.

Thanks