1. As long as your groups are balanced you are probably ok, although ideally you would scan the same subject on both scanners to assess the differences.

2. Not easily, although we have some tools for doing this. They aren't packaged and distributed though.

3. Yes, this probably makes a difference. Again, if your groups are balanced you are probably ok, but the variance may increase

cheers, Bruce On Fri, 28 Sep 2007, Pedro Paulo Oliveira Jr wrote:

I have some methodological doubts and I think somebody can give a hint.

1.  I have read the paper from Neuroimage 2006 comparing Scanner, Field
   

Strength, etc in thickness measurements. Is it possible to assume that we can mix in our study group images that come from different MRI Scanners?

2.  We have some very high resolution histological data of full brain
   

and correspondent MRI images also acquired post-mortem. Is it possible to use histological data in FreeSurfer or just SPGR?

3.  Does slice thickness affect group studies. I mean we have some
   

subjects with slice thickness 0.6mm and other with 0.8mm.

Thanks in advance,

Pedro Paulo Oliveira Jr.