Risk of bias assessment across studies
| Bang et al 20 | Carlo et al 17 | Carlo et al 18 | Gill et al 21 | Zhu et al 26 | Deorari et al 24 | Jeffery et al 28 | O’Hare et al 25 | Opiyo et al 19 | Boo31 | Sorensen et al 29 | Hole et al 32 | Msemo et al 22 | Goudar et al 23 | Vossius et al 77 | Ashish et al (Unpublished data) | Bellard et al | Patel et al (Unpublished data) | |
| Adequate sequence generation? | High risk | Low risk | ||||||||||||||||
| Allocation concealment? | High risk | Low risk | ||||||||||||||||
| Incomplete outcome data addressed? | High risk | Low risk | Low risk | Low risk | Unclear risk | Unclear risk | Unclear risk | Low risk | Unclear risk | Low risk | Low risk | High risk | Unclear risk | Unclear risk | Low risk | Low risk | Low risk | Low risk |
| Free of selective reporting? | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk |
| Free of other bias? | Unclear risk | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | Unclear risk | Unclear risk | Uncleat risk | Low risk | Unclear risk | Low risk | Unclear risk | High risk | Low risk | High risk | Unclear risk |
| Baseline outcomes similar? | Low risk | Low risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | unclear risk | Uncleat risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | ||
| Free of contamination? | Low risk | Low risk | Low risk | Low risk | Unclear risk | Low risk | Low risk | High risk | Low risk | High risk | Low risk | Low risk | High risk | Low risk | Low risk | Low risk | ||
| Baseline characteristics similar? | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Unclear risk | Low risk | Low risk | Unclear risk | Unclear risk | Low risk | Unclear risk | High risk | Low risk | Low risk |