I'm not sure how to do this in the RM ANOVA framework. Since you only have two time points, why not just compute their difference then use a typical design?

On 10/11/19 2:34 PM, miracle ozzoude wrote:

External Email - Use Caution

Hello Experts,

I would like to include covariates in the freesurfer repeated anova steps https://surfer.nmr.mgh.harvard.edu/fswiki/RepeatedMeasuresAnova. When i tried including 3 covariates, mri_glmfit complained about "martix is ill-conditioned".

How do i fix it?

Below is an example my fsgd file. I've also attached the matrix design in the email.

GroupDescriptorFile 1 Class PsyDis1 Class PsyDis2 Variables TP1vsTP2 Age Llesion Rlesion Input Psy1_Pre.long.Psy1 PsyDis1 1 68 96 61 Input Psy1_6mos.long.Psy1 PsyDis1 -1 68 96 61 Input Psy2_Pre.long.Psy2 PsyDis2 1 39 217 140 Input Psy2_6mos.long.Psy2 PsyDis2 -1 39 217 140

contrast: 0 0 1 0 0

Best, Paul

_______________________________________________ Freesurfer mailing list Freesurfer@nmr.mgh.harvard.edumailto:Freesurfer@nmr.mgh.harvard.edu https://mail.nmr.mgh.harvard.edu/mailman/listinfo/freesurfer