- Cochrane risk of bias assessment for included studies.
| Studies | Random sequence generation | Allocation concealment | Blinding of participants and personnel | Blinding of outcome assessment | Incomplete outcome data | Selective reporting | Other bias |
|---|---|---|---|---|---|---|---|
| Bordini et al14 | Low | Low | High | High | Low | Low | High |
| Carlisle et al15 | Unclear | Unclear | High | High | Low | Low | High |
| Chien et al16 | Unclear | Unclear | Low | High | High | Low | High |
| Clifford et al17 | Low | High | High | High | High | Low | High |
| Corbett et al18 | Low | Unclear | High | High | High | Low | High |
| Grahame et al19 | Low | Unclear | High | Low | Low | Low | High |
| Ko et al20 | Low | Unclear | High | Low | High | Low | High |
| LaGasse et al21 | Low | Unclear | High | High | Low | Low | High |
| Levin et al22 | Unclear | Unclear | High | Unclear | High | Low | High |
| Thompson et al23 | Low | Low | High | High | Low | Low | High |
| Fletcher-Watson et al24 | Low | Low | High | High | High | Low | High |
| Wood et al25 | Unclear | Unclear | High | Low | High | Low | High |
| Wood et al26 | Low | Low | High | High | High | Low | High |
| Yoder et al27 | Low | Unclear | High | Unclear | Low | Low | High |
| Young et al28 | Low | Unclear | High | Low | High | Low | Low |
| Zheng et al29 | Low | Unclear | High | Unclear | Low | Low | High |
| Zhou et al30 | Unclear | Unclear | High | Low | Low | Low | High |