Table 2 Risk of bias in included studies
Author/year | Randomization | Allocation concealment | Blinding of participants | Blinding of outcome assessment | Incomplete outcome data | Selective outcome reporting | Other bias |
|---|---|---|---|---|---|---|---|
Fan 2014 | Low | Unclear | Low | Low | Low | Low | Unclear |
Hakkalamani 2015 | Low | Low | Low | Low | Low | Low | Unclear |
Harvey 1997 | Unclear | Unclear | Low | Low | Low | Low | Unclear |
Kvederas 2013 | Low | Low | Low | Low | Low | Low | Unclear |
Mittal 2012 | Low | Low | Low | Low | Low | Low | Unclear |
Tarwala 2014 | Low | Unclear | Low | Low | Low | Low | Unclear |
Wang 2016 | Low | Low | Low | Low | Low | Low | Unclear |