hi all,
I have a optimized and modulated vbm study with cases and controls, I want
to compare for gm reduction in cases.
I have choosen PET model Ancova (compare two populations) and I have two
nuisances, global brain volume and age.
How to set contrast for controls>cases eliminating effects due two global
volume and age? 1 -1 0 1 1 or 1 -1 0 0 0?
On the other hand is it possible possible with this model to see if any
correlation between a found decrease in gm and the two covariates or
others?
Thanks
Riccardo
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