Table 2 Details of quality evaluation for the included RCTs according to the Cochrane’s Risk of Bias Tool
Study | Random sequence generation | Allocation concealment | Blinding of participants | Blinding of outcome assessment | Incomplete outcome data addressed | Selective reporting | Other sources of bias | Total |
|---|---|---|---|---|---|---|---|---|
Jing 2011 | Low | Unclear | Low | Low | Low | Low | Low | 6 |
Joung 2013 | Low | Unclear | Low | Low | Low | Low | Low | 6 |
Meybohm 2013 | Unclear | Low | Low | Low | Low | Low | Low | 6 |
Hudetz 2015 | Unclear | Low | Low | Low | Low | Low | Low | 6 |
Meybohm 2015 | Low | Low | Low | Low | Low | Low | Low | 7 |
Brown 2016 | Unclear | Unclear | Low | Low | Low | Low | Low | 5 |
Kim 2017 | Low | Low | Low | Low | Low | Low | Low | 7 |
Meybohm 2018 | Low | Low | Low | Low | Low | Low | Low | 7 |
Wang 2019 | Low | Unclear | Low | Low | Low | Low | Low | 6 |
Gasparovic 2019 | Low | Low | Low | Low | Low | Low | Low | 7 |