| Author and year | Random sequence generation (selection bias) | Allocation concealment (selection bias) | Blinding of participants and personnel (performance bias) | Blinding of outcome assessment (detection bias) | Incomplete outcome data (attrition bias) | Selective reporting (reporting bias) |
| Patel et al., (2006) | Not clear | Not clear | Low risk | High risk | Low risk | Low risk |
| Lee et al., (2012) | Low risk | Not clear | Low risk | High risk | Low risk | Low risk |
| Mifflin et al., (2012) | Low risk | Low risk | Low risk | High risk | Low risk | Low risk |
| Kerimoglu et al., (2013) | Low risk | Low risk | Low risk | High risk | Low risk | Low risk |
| Seiden et al., (2014) | Not clear | Not clear | High risk | Low risk | Low risk | Low risk |
| Kim et al., (2015) | Low risk | Not clear | Low risk | High risk | Low risk | Low risk |
| Sola et al., (2017) | Low risk | Low risk | Low risk | High risk | Not clear | Low risk |
| Marechal et al., (2017) | Low risk | Low risk | High risk | High risk | Low risk | Low risk |