HI, I solve my problem. The FreeSurfer GLM model is easier to use than SPSS GLM. I had force SPSS to look at my model by selecting group differences between group1 and group2 and look at interactions between the three groups. I then got similar results as in FreeSurfer glm for the group differences
Best regards Knut J On 07/31/2012 09:37 AM, Knut J Bjuland wrote: > Hi, > I have calculated the group differences for volume using both > FreeSurfer GLM and SPSS GLM. I have used gender and group as fixed > factor and intercranial volume and age at MRI scan as covariate. > > GroupDescriptorFile 1 > Title group_difference_between_group1_and_group2_gender_age > DeMeanFlag 1 > Class Group2Male > Class Group2Female > Class Group1Male > Class Group1Female > Variables ICU Age > > I used this as fsgd heading, and I used this contrast vector 0.5 0.5 > -0.5 -0.5 0 0 0 0 0 0 0 0 to be able to control for gender difference > and difference due to age and ICU. I get difference results between SPSS > and Freesurfer. I think this is strange since I used the same data both > in FreeSurfer GLM and SPSS glm. Is there anything I have done wrong? I > have used both univariate and multivariate in SPSS glm. > > Best regards > Knut J > _______________________________________________ > Freesurfer mailing list > Freesurfer@nmr.mgh.harvard.edu > https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer > > > The information in this e-mail is intended only for the person to whom it is > addressed. If you believe this e-mail was sent to you in error and the e-mail > contains patient information, please contact the Partners Compliance HelpLine > at > http://www.partners.org/complianceline . If the e-mail was sent to you in > error > but does not contain patient information, please contact the sender and > properly > dispose of the e-mail. > > > _______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer