The recent paper by Wonderlick et al. (Neuroimage 44:1324-1333, 2009) is relevant to your situation. They show that differing voxel geometry can definitely lead to bias in the results (as Bruce noted).
cheers, Mike H. On Tue, 2009-03-17 at 21:26 -0600, Jeff Sadino wrote: > Hi Bruce, > > Yes, we are going to combine them into a single study. Is there a > place on the wiki I can read about how to error check for these > problems? > > Thank you, > Jeff > > > Date: Tue, 17 Mar 2009 19:39:34 -0400 > > From: fis...@nmr.mgh.harvard.edu > > To: jsad...@hotmail.com > > CC: freesurfer@nmr.mgh.harvard.edu > > Subject: Re: [Freesurfer] Changing from 1.4x1.4x1.4 mm slices to > 1x1x1 > > > > Hi Jeff, > > > > are you intending to combine them into a single study? This can be > > problematic as you'll get differential sensitivity and possibly > bias. > > > > cheers, > > Bruce > > > > On Tue, 17 Mar 2009, Jeff Sadino wrote: > > > > > > > > Hello, > > > > > > I am analyzing some subjects from several years ago when we had a > protocol that called for slices 1.4x1.4x1.4mm. I am also including in > the study more recent scans with a protocol for 1x1x1mm slices. I am > using freesurfer 3.0.5. I am wondering if the different slice > dimensions will cause differences in the analysis. As I read on a > previous post, freesurfer resamples all its input data into 1mm > isovolumetric voxels anyways, so I should be ok? > > > > > > Regards, > > > Jeff Sadino > > > > > > _________________________________________________________________ > > > Hotmail® is up to 70% faster. Now good news travels really fast. > > > http://windowslive.com/online/hotmail? > ocid=TXT_TAGLM_WL_HM_70faster_032009 > > > ______________________________________________________________________ > Windows Live™: Keep your life in sync. Check it out. > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer
