Dear Freesurfer experts,
I am modelling multiple covariates (age, SES, nr of symptoms and nr of symptoms2) in one subject group. For the quadratic term I added a column in the fsgd-file. I want to visualize the effect of nr of symptoms, either their linear or their quadratic effects. I therefore made two contrasts: The effect of symptoms: 0 0 1 0 And the effect of symptoms2: 0 0 0 1 I would like to model these two effects together in one contrast (to get the results of both contrasts overlaid on top of each other, but in one mgh file). I tried the following contrast: 0 0 1 0 0 0 0 1 But the result is very different from the two individual contrasts. I get large (non-overlapping) clusters of significant effect in the two separate contrasts, but with the combined contrasts I get none. In the examples I found online for F-contrasts, they always add up to zero, as they are comparisons between groups. What would be the appropriate contrast if I want to visualize all regions with EITHER a linear OR a quadratic effect of symptoms? Thank you very much for your help! Best wishes, Lizanne
_______________________________________________ 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.
