Do three or more groups differ on average?

How to run and report anova in APA 7

One-way ANOVA extends the t-test to more than two groups, testing whether at least one group mean differs — without inflating the error rate that running several t-tests would cause.

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When to use it

  • •You have three or more independent groups.
  • •Your outcome is continuous.
  • •You want an omnibus test before looking at specific pairs.

Assumptions to check first

  • •Independent observations across groups.
  • •Approximately normal outcome within each group.
  • •Homogeneity of variance (Welch's ANOVA is the fallback when this fails).

What to report

  • •F with both degrees of freedom (between and within), and the exact p.
  • •An effect size — η² or partial η².
  • •Descriptives for every group.
  • •Post-hoc comparisons with the correction used (Tukey, Bonferroni, etc.), but only if the omnibus test warrants them.

APA 7 example

Department had a significant effect on engagement, F(3, 196) = 7.82, p < .001, η² = .11. Tukey post-hoc comparisons showed Sales scored significantly lower than R&D (p = .002) and Marketing (p = .014).

Numbers are illustrative — the Advisor generates this sentence with your own results.

The mistake reviewers catch

A significant F tells you that some group differs — not which one. Jumping straight to pairwise t-tests without a correction is exactly the error ANOVA exists to prevent.

Run it on your own data

Paste or upload your dataset — nothing leaves your browser. The Analysis Advisor checks the assumptions above, runs anova, and drafts the APA Methods and Results text with your numbers in it.

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Frequently asked questions

When should I use anova?

Do three or more groups differ on average? You have three or more independent groups.

What do I need to report for anova in APA 7?

F with both degrees of freedom (between and within), and the exact p. An effect size — η² or partial η². Descriptives for every group. Post-hoc comparisons with the correction used (Tukey, Bonferroni, etc.), but only if the omnibus test warrants them.

What is the most common mistake with anova?

A significant F tells you that some group differs — not which one. Jumping straight to pairwise t-tests without a correction is exactly the error ANOVA exists to prevent.