I have what I think is a very elementary question about the results of a repeated measures ANOVA.

Say that there are two factors of interest (independent variables, 3 treatments and 3 years) and their interaction incorporated into the model.

If there is a significant treatment effect, but no significant interaction, is it still appropriate to do pairwise comparisons of the groups within one year, or am I only limited to interpreting the main effects of treatments?

For example, there was a significant treatment effect, but no interaction. However, I wanted to know if there was a difference between the treatments for each particular year before I ran the ANOVA. Is it still appropriate to interpret the differences between treatments for a particular year even though there was no interaction of treatment and year?

I hope that question was not too confusing. If so, I'll try again.