I have three experimental and one control group in my study. I have two observations for them (pre and post test). I want compare four group in those 2 observations.
I choose to do "Repeated Measures-ANOVA" analysis. However i have two questions:
1) Which contrast should i choose here? Polynomial is okay? 2) Which post-hoc test should i use? I did an example with Bonferroni and it seems okay. Although some researchers suggest Tukey Hsd, can i compare all four groups in Repeated Measures menu / Post-hoc / choose Tukey or Bonferroni. Or should i perform Tukey test manually?