I am measuring secretion of insulin upon glucose stimulation of pancreatic islets after various treatments. So I have two independent variables/factors:
- Treatment (three different compounds and a control treatment)
- Glucose concentration (low and high)
My sample size is only 3 to 4 individuals per experimental group.
I analyzed the data by two-way ANOVA (using Prism for Mac), confirming that the effects of the two factors are not independent. Now I am unsure about what test I should choose to do pairwise comparisons of each treatment vs. the control.
Prism allows for including Bonferroni's post-hoc tests, after quickly checking the Wikipedia article about ANOVA, I believe Dunnett's test might be appropriate, but I have seen publications using Duncan's test, Tukey's test as well as Student's t test for pairwise comparisons in similar setups.
Having no suitable textbook at hand, and since I didn't find a good descriptive example from the life sciences/biology field online, I am not sure what test is appropriate.
Can someone point me to some material (or recommend a good textbook) that guides the experimenter which (post-hoc/a priori) test to use, and ideally explains why?