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A comparison of three hypothetical measures and their associated study sample sizes, costs and study durations
| Example 1 | Example 2 | Example 3 | |
|---|---|---|---|
| α | 0.05 | 0.05 | 0.05 |
| β | 0.20 | 0.20 | 0.20 |
| SD | 10 | 10 | 8 |
| Expected difference between group means (Δ) | 10 | 2.5 | 2.5 |
| Effect Size | 1 | 0.25 | 0.3125 |
| Sample Size | 16 | 256 | 164 |
| Cost ($1500/participant) | $24,000 | $384,000 | $246,000 |
| Time to complete study (10 participant/month) | 1.6 months | 25.6 months | 16.4 months |
