ANOVA Statistical test

What is ANOVA?

ANOVA (Analysis of Variance) is a statistical test that compares means across three or more groups to determine if at least one group differs significantly.

Types

One-Way ANOVA

• One independent variable with 3+ levels
• Example: Comparing metabolite levels across 3 cohorts

Two-Way ANOVA

• Two independent variables
• Example: Effect of treatment and sex on outcome

Interpretation

• Significant F-test: At least one group differs
• Post-hoc Tests: Determine which groups differ (e.g., Tukey HSD)

Assumptions

• Continuous dependent variable
• Independent observations
• Approximately normal distributions
• Homogeneity of variances

Related Terms

• T-Test: Compares only two groups
• P-Value: Significance of the F-test