I have 6 Treatment groups (A-F, with A as control) and measure parameter A at four time points 1-4. Now I am particular interested in
time*treatment as I want to know if the change over time of the parameter of the groups B-F is significantly different to the control A. However, with a mixed multiple measures ANOVA including all groups (A-F) I only get a general answer:
time*treatment is significant or not. Consequently, I did mixed multiple measures ANOVA for each group and the control group (A and B, A and C, A and D etc.).
My question now: Is it appropriate to do seperate analyses? (I am thinking of the issue with multiple t-test and the increase in type 1 error)
Is there another way to calculate the
time*treatment significancies for all groups (B-F) to the control within a single analysis?
I am working with SPSS btw. - Thank you already in advance!
EDIT: This is a repeated measures ANOVA with one dependent variable and not a MANOVA where you have multiple independent variables