A study compares three independent groups on a continuous outcome and assumes normality. Which test is most appropriate?

A study compares three independent groups on a continuous outcome and assumes normality. Which test is most appropriate?

• A. One-factorial ANOVA
• B. Kruskal-Wallis Test
• C. Wilcoxon
• D. Paired t-test

Answer: (A)

When you’re comparing means across more than two independent groups with a continuous outcome and you can assume normal distribution, the appropriate test is a one-way ANOVA. It assesses whether the group means differ overall by comparing between-group variance to within-group variance. If the ANOVA yields a significant result, you can follow up with post-hoc pairwise comparisons (like Tukey) to identify exactly which groups differ, while controlling for multiple comparisons. Kruskal-Wallis is a nonparametric alternative used when normality isn’t assumed; Wilcoxon is for nonparametric comparisons and typically for two related or two independent samples depending on the variant; and the paired t-test is for related or matched samples, not independent groups. So with three independent groups and normality, one-way ANOVA is the best choice.

When you’re comparing means across more than two independent groups with a continuous outcome and you can assume normal distribution, the appropriate test is a one-way ANOVA. It assesses whether the group means differ overall by comparing between-group variance to within-group variance. If the ANOVA yields a significant result, you can follow up with post-hoc pairwise comparisons (like Tukey) to identify exactly which groups differ, while controlling for multiple comparisons. Kruskal-Wallis is a nonparametric alternative used when normality isn’t assumed; Wilcoxon is for nonparametric comparisons and typically for two related or two independent samples depending on the variant; and the paired t-test is for related or matched samples, not independent groups. So with three independent groups and normality, one-way ANOVA is the best choice.