Hello,

I'm struggling with applying the Bonferroni correction in my analysis, more specifically figuring out the number of comparisons I have to control for.

I have several statements which participants (divided into three independent groups) rated on a ordinal scale. I'm interested if there are differences for each statement between the groups. For that purpose, I performed a Kruskal-Wallis H test with Dunn's post-hoc test and a corrected alpha level of 0.05/3 for each statement (as I do not draw comparisons between statements). Now I'm wondering if the correction should rather take all pair-wise comparisons across all statements (0.05 / (nr of statements x 3)) into account in order to control for false-positives across the whole analysis?

EDIT: After thinking about it again, would it also make sense to control for the multiple Kruskal-Wallis H test in the first place? If so, how could that be accomplished?

Thank you in advance!

I'm struggling with applying the Bonferroni correction in my analysis, more specifically figuring out the number of comparisons I have to control for.

I have several statements which participants (divided into three independent groups) rated on a ordinal scale. I'm interested if there are differences for each statement between the groups. For that purpose, I performed a Kruskal-Wallis H test with Dunn's post-hoc test and a corrected alpha level of 0.05/3 for each statement (as I do not draw comparisons between statements). Now I'm wondering if the correction should rather take all pair-wise comparisons across all statements (0.05 / (nr of statements x 3)) into account in order to control for false-positives across the whole analysis?

EDIT: After thinking about it again, would it also make sense to control for the multiple Kruskal-Wallis H test in the first place? If so, how could that be accomplished?

Thank you in advance!

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