I have three independent variables (2 treatment & 1 control) and 1 dependent variable (a test score). N will be 30 or so. I'm planning on doing a one-way ANOVA & Tukey or Tukey Kramer (depending on the actual N) as my post hoc comparisons.

After I collect my data, I would like to conduct a test that looks to see if there is any significance between low and high performers (50% split) based upon the test score. So here are my questions:

1. Is comparing based upon the two groups appropriate?

2. Is this properly called a split-wise comparison?

3. Would the placement in low/high gropuing be a dependent or independent variable?

4. Would I be conducting a two-way ANOVA to do this?

Thank you in advance!