I have the following dilemma:

Design: 1 (Group: Patient vs. Control_1 vs. Control_2) between-factors design arrayed as a 1-way ANOVA

Analysis: Following a main effect of group perform I perform all pairwise comparisons using Tukey tests.

Question: Cohen's d for paired comparisons is the mean difference divided by the pooled standard deviation. This information is not available for Tukey tests. Is there a way to compute Cohen's d or a standardized effect size from these data?


1 Answer 1


You can easily compute Cohen's $d$ using the three means and ANOVA output. The square-root of the MS-error (or MS-residual depending on which program you used) is the pooled within-groups standard deviation. Thus, simply divide each mean difference by this value.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.