Hello there,

I have a question about 3dMVM and covariates

My 3dMVM analysis has two within subjects factors - load (3 levels )and chromophore (2 levels). These are data from infants and children of different ages, but each infant/child has a value for each level of a factor. We think that our effects be it main effect of load and/or main effect of chromophore and/or interaction between load and chromophore might be driven by Age. Hence , we would like to use Age (in days) as a covariate. In this case, do I need to center Age with qVarsCenters) ? It would seem unnecessary as an average of the ages for each load and/or chromphore would be the same.

Does this seem accurate?

Any advice is appreciated.

Thank you.

Sobana