Table 5 Sample size required for the two different approaches, binomial and lognormal, under different scenarios, for a one-sided 5% significance test with 80% power for relative risk (RR)
From: Prevention of postpartum haemorrhage: a distributional approach for analysis
Scenario | Assumed sPPH rate for control (%) | RR | Total sample size with the binomial approach | Total sample size with the lognormal approach |
|---|---|---|---|---|
1 | 1.5 | 0.70 | 15,294 | 1178 |
2 | 1.5 | 0.80 | 36,522 | 3068 |
3 | 2.0 | 0.70 | 11,422 | 1080 |
4 | 2.0 | 0.80 | 27,266 | 2814 |
5 | 2.5 | 0.70 | 9098 | 1002 |
6 | 2.5 | 0.80 | 21,714 | 2618 |