| Items | Author | ||||
| Baldwin- 2012 | Katona - 2012 | Boulenger- 2013 | Mahableshwarkar -2013 | Mahableshwarkar- 2014 | |
| Random sequence generation (selection bias) | L | L | L | L | L |
| Allocation concealment (selection bias) | L | L | L | L | L |
| Blinding of participants and personnel (performance bias) | L | L | L | L | L |
| Blinding of outcome assessment (detection bias) | L | L | L | L | L |
| Incomplete outcome data (attrition bias) | L | U | U | U | U |
| Selective reporting (reporting bias) | L | U | L | L | L |
| Other bias | U | U | L | U | U |