Table 1.
Baseline characteristics of the included studies and methodological assessment.
| Authors | Study period | Countries | Study design | Maternal participants | Infant participants |
|---|---|---|---|---|---|
| Vaccine/Placebo | Vaccine/Placebo | ||||
| Kampmann et al. (27) | 2020–2022 | 18 countries | RCT | 3,682/3,675 | 3,568/3,558 |
| Bebia et al. (28) | 2019–2021 | 9 countries | RCT | 145/68 | 140/66 |
| Simões et al. (29) | 2019–2020 | 4 countries | RCT | 327/79 | 325/78 |
| Lewnard et al. (30) | 2015–2018 | 11 countries | RCT | 3005/1,573 | 2,978/1,546 |
| Madhi et al. (31) | 2015–2018 | 87 countries | RCT | 3,045/1,581 | 3,008/1,561 |
| Muňoz et al. (32) | 2014–2015 | 8 countries | RCT | 22/28 | 22/28 |