Dear Guillaume, dear Christian,
thank you for your advice regarding the design. I see the example in the CAT12 manual for longitudinal data in two groups, but I was wondering why you exclude the main effects of group and time in your model and include the interaction of group x time only. Following the tutorial of Jan Gläscher and Darren Gitelman for flexible factorial designs (originally for SPM5), I thought that the inclusion of main effects should increase sensitivity for an interaction effect (find attached, page 11). Could you please comment on that?
Best regards,
Dario
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