[SOLVED] Reverse Psychology

I have a rather unique problem. All the hypotheses I've come across in psychology statistics test for a significant difference between two or more groups. However, I need to test for the *absence* of a significant difference between two groups. In other words, my hypothesis states that there is *no significant difference* between my two groups.

I am using the Wilcoxon Signed-Rank Test. I know how to run this particular test, but I am unclear on one point.

The typical hypothesis states that a difference exists between the groups. In this case, the researcher rejects the null hypothesis when the test value is equal to or less than the critical value.

Does that mean that in my case, where my hypothesis states that a difference *does not* exist, I reject the null hypothesis if the test value is *greater* than the critical value?

**SOLUTION:** I need to employ an Equivalence Test in this situation. See Statistical tests for equivalence.