Dear all,
I've recently started with SPM and i have a very simple question to ask.
I have to compare 2 conditions (patients and controls) using “Basic models –
Ancova”; I would include in the model grey matter (gm) as covariate, and
total intracranial volume (tiv) as nuisance.
If I choose
- “Basic models – Ancova”
- “2 groups”: I choose smoothed modulated grey matter images because I’m
interested in grey matter volume
SPM2 ask me for nuisance only (tiv in this case), and not for covariates too.
Obviously in the matrix design parameters are:
2 conditions
0 covariates
1 block
1 nuisance.
Probably I messed up something. I don’t know how to enter grey matter volume
as covariate. Anyone could help me?
Thank you
Luc
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