Which ANOVA?

Hi there :)

I am struggling to determine which would be the most appropriate ANOVA analysis to use for some work I am doing.

I have 3 independent groups: control, CBT group, and CBT + antidepressant group.
For each individual, there are 2 pieces of data- before and after treatment.

My research questions are:
Does CBT reduce symptoms of depression?
Does adding antidepressant treatment to CBT further reduce symptoms of depression?

I am confused as to what sort of ANOVA analysis to conduct- one way ANOVA? Multifactorial? And what contrasts to plan?

Any help would be greatly appreciated! :)


Well-Known Member
One simple approach is to find the before/after difference for each subject. Then a one way anova on these differences will tell you if there is a significant difference between at least 2 of the 3 groups. if there is a significant difference somewhere, post hoc tests will tell you which groups can be considered different.