Question

what kind of research study produces data appropriate for the Wilcoxen test

Answer 1

Use this when the same participants perform both conditions of your study: i.e.,

a) it is appropriate for analyzing the data from a repeated-measures design with two conditions.

b)

Use it when the data do not meet the requirements for a parametric test

i)   if the data are not normally distributed;

ii) if the variances for the two conditions are markedly different; or

iii) if the data are measurements on an ordinal scale

Otherwise, if the data meet the requirements for a parametric test, it is better to use a repeated measures t-test (also known as a "dependent means" or "matched pairs" t-test).