🔄 Repeated Measures ANOVA Calculator
Repeated Measures ANOVA Calculator
Analyze the same subjects measured across multiple conditions or time points. Perfect for before-after studies and longitudinal data.
Enter Your Data
Each row = subject, each column = time point or condition. All subjects must have complete data.
When to Use Repeated Measures ANOVA
Use Cases
- Before-After Studies: Measuring the same people before, during, and after treatment
- Longitudinal Studies: Following subjects over time (e.g., anxiety at months 1, 3, and 6)
- Repeated Tests: Same subjects taking multiple forms of a test
- Multiple Measurements: Blood pressure measured multiple times daily
Key Characteristics
- The same subjects are measured multiple times
- Measurements are typically correlated (not independent)
- Controls for individual differences between subjects
- Provides more statistical power than independent samples
Example
A researcher tests the effect of a stress-reduction program. She measures anxiety scores for 5 subjects at three time points: Before treatment, After 4 weeks, and After 8 weeks.
| Subject | Pre | Week 4 | Week 8 |
|---|---|---|---|
| 1 | 78 | 72 | 65 |
| 2 | 82 | 75 | 68 |
| 3 | 75 | 70 | 60 |
| 4 | 80 | 74 | 66 |
| 5 | 79 | 73 | 64 |