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Study sample size calculated using the EPIDAT program
| Power (%) | Sample size* (+ correction factor for expected losses) | ||
|---|---|---|---|
| EG | CG | Total | |
| 80.0 | 854 | 854 | 1708 |
Sample sizes to apply the χ2 test with Yates continuity correction
*An α risk of 0.05 and a β risk of 0.2 (80% power) are assumed, standard values in such studies
