Hey Gang,
Thanks for the response. I'm surprised that I should treat a quantitative score of symptom severity as a between subject factor since its not a group factor. Perhaps there is a confusion because I am currently only running the analysis on a subset of data just to learn how to 3dMVM. The full data set will have 40 subjects with symptom severity scores ranging anywhere between 0 to 20. Should I still treat this variable as between subject or as a quantitative variable when I have a full complement of subjects?
