Hi list,
I have done an analysis using QDEC and now I would like to do set up similar statistical analysis in SPSS on some parcellated structures.
I have the following setup in QDEC:
2 cohorts (patients, healthy control subjects) Continuous variable : demeaned Age Nuisance Factor: demeaned intracranial volume DODS
I'm interested in the effect of age i.e. "differences in the thickness-age correlation between the patients and healthy subjects" . Now my question is if I the following set up would be correct for doing the stats on slopes in SPSS:
Univariate General Linear Model Dependent variable: ROI Fixed Factor: group (i.e. patient or healthy control) Covariate: demeaned age AND demeaned intracranial volume
and then I also add an interaction term of demeaned_age*group to be the equivalent to the difference between thickness-age correlation in patients vs. healthy subjects that I have in QDEC. Is this correct?
Thanks, Nasim