I counducted a mixed model ANOVA with time as the within subjects variable (3 levels) and group as the between subjects variable (2 levels). All is significant (time, group, and timeXgroup). To test if differences over the three times are significant in both groups, I conducted two separate repeated measures ANOVAs, one for each group, with time (3 levels) as the withing subjects variable.
I have a problem with the control group, because ANOVA for this group is slightly significant (p = 0.044) but the multiple comparisons with Bonferroni correction are all not significant... Indeed, in the graph I can see that the differences across time are not very big. However I don't know how to explain this result... Can you help me?
I try to explain myself better so maybe you can understand my situation. These are the descriptive statistics:
Control group (N=10)
1st measure 2.40 (1.36)
2nd measure 2.87 (1.57)
3rd measure 2.55 (1.48)
Experimental group (N=10)
1st measure 3.04 (1.14)
2nd measure 6.71 (3.52)
3rd measure 4.64 (1.76)
As you can see the control group has a small change over time, the experimental group instead has a big change. I ran the mixed 2x3 ANOVA to see if the two groups were significantly different and if there was an interaction. Since all was significant, I wanted to see if both group differ significantly over time or only the experimental group. Thank you!