Repeated measures with a continuous between-subject variable
I'm trying to build a repeated measures model (called levels in the next description) where I have two-between subjects variables, one being nominal (gender, two levels) and one being a continuous variable (a score at a particular questionnaire).
I tried with ANOVA, but the continuous measure can only be used as covariate. As a result, I cannot get the 3-way interaction that I'm interested in (gender * questionnaire score * levels).
Is there a way to build such a model? what would be, eventually, the way to set it up?
thanks in adance