Yes, that looks correct. Since you have a covariate as a nuisance variable, you should first run your analysis with a DODS model (different-offset, different-slope) and look for an interaction between your group variables and age (the contrasts are similar, swap the first 6 numbers with the last 6 zeros). If you do not find an interaction, then re-run the analysis with DOSS and use a contrast that has 7 numbers: the first 6 as you have given, the last number = 0.

doug

ZhiLiangLong wrote:

Hi all : I'm performing general linear model (GLM) analysis in the surface,the attachments above are FSGD file and contrast files(the last three attachments).i wonder if my contrast files are correct. the attachment named diff-C-H-thickness.txt is about difference between C and H and the last two are about difference between C and p and difference between P and H,Here,C H and P represent three groups Any suggestions appreciated

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