Table 1 Statistical power for primary outcomes of preeclampsia and preterm birth for each trial site based on a one-sided test with a type I error rate of 0.05 (India = 11,000 participants; Tanzania 11,000 participants)
|  | Cumulative incidence of preeclampsia in standard high-dose calcium group (1500 mg/day) | |||
|---|---|---|---|---|
1.5% | 3% | 5% | ||
Statistical power for preeclampsia | Noninferiority margin—relative risk of 1.54 | 95.3% | 99.9% | > 99.9% |
|  | Proportion of preterm (< 37 weeks) in standard high-dose calcium group (1500 mg/day) | |||
10.0% | 12.5% | 13.5% | ||
Statistical power for preterm birth | Noninferiority margin—relative risk of 1.16 | 84.3% | 91.4% | 93.3% |