Risk of bias of the included studies
| Study | Random sequence generation | Allocation concealment | Blinding of participants and personnel | Blinding of outcome assessment | Incomplete outcome data | Selective reporting | Other bias |
| UCM vs DCC | |||||||
| Rabe et al 17 | Low | Low | High | Low | Low | Low | Low |
| Katheria et al 16 | Low | Low | Low | Low | Low | High* | High† |
| Shirk et al 18 | Low | Low | High | High | High‡ | Low | Low |
| Finn et al 15 | Low | Low | High | Low | Low | Low | High§ |
| Katheria et al 8 | Low | Low | Low | Low | Low | Low | High¶ |
| UCM vs ICC | |||||||
| Hosono et al 22 | Unclear | Low | High | Low | Low | Low | Low |
| March et al 29 | Low | Low | High | Low | High** | Low | High¶ |
| Alan et al 19 | Unclear | Low | High | Low | Low | Low | Low |
| Josephsen et al 23 | Unclear | Unclear | Unclear | Unclear | Low | Unclear | Unclear |
| Katheria et al 24 | Unclear | Low | High | Low | Low | Low | Low |
| Kumar et al 26 | Low | Low | High | High | Low | Low | Low |
| Kilicdag et al 25 | Unclear | Low | Unclear | Unclear | Low | Low | Unclear†† |
| Song et al 32 | Low | Unclear | Unclear | Low | Low | Low | Low |
| Alavi et al 20 | High‡‡ | High | Unclear | Unclear | Low | Low | Unclear†† |
| El-Naggar et al 21 | Low | Low | Low | Low | Low | Low | High† |
| Lago Leal 201827 | Unclear | Low | Low | Low | Low | Low | Low |
| Li et al 28 | Unclear | Unclear | Unclear | Low | Low | Low | Low |
| Ram Mohan et al 30 | Low | Low | High | High | Low | Low | Low |
| Silahli et al 31 | Low | Low | High | Low | Low | Low | Low |
*Outcomes reported only for 154 caesarean delivered neonates, no outcomes reported for 43 vaginally delivered infants.
†Crossover rate of >10% in DCC arm.
‡27% infants excluded after randomisation.
§Underpowered for the primary outcome.
¶Study discontinued after second interim analysis, incomplete sample size).
**Pregnancies continuing beyond 28 weeks were excluded after randomisation.
††Sample size calculation not mentioned.
‡‡First 40 patients were milked, next 40 patients received ICC.