Table 2 Risk of bias in published randomized control trials
Study | Random sequence generation | Allocation concealment | Blinding of participants and personnel | Blinding of outcome assessment | Incomplete outcome data | Selective reporting | Other bias | Score |
|---|---|---|---|---|---|---|---|---|
Gadallah 1999 [16] | UC | UC | Low risk | Low risk | Low risk (Loss to follow-up: 0) | Low risk | Low risk | 5 |
Wright 1999 [14] | Low risk | Low risk | Low risk | Low risk | Low risk (Loss to follow-up: 0) | Low risk | Low risk | 5 |
Tsimoyiannis 2000 [10] | Low risk | Low risk | Low risk | Low risk | Low risk (Loss to follow-up: 3/50) | Low risk | Low risk | 7 |
Jwo 2010 [12] | UC | UC | Low risk | Low risk | Low risk (Loss to follow-up: 0) | Low risk | Low risk | 5 |
Laanen 2018 [17] | Low risk | Low risk | Low risk | Low risk | Low risk (Loss to follow-up: 5/95) | Low risk | Low risk | 7 |
Qiao 2012 [18] | UC | UC | Low risk | Low risk | Low risk (Loss to follow-up: 6/116) | Low risk | Low risk | 5 |
Qu 2017 [19] | UC | UC | Low risk | Low risk | Low risk (Loss to follow-up: 0) | Low risk | Low risk | 5 |
Xu 2010 [20] | UC | UC | Low risk | Low risk | Low risk (Loss to follow-up: 0) | Low risk | Low risk | 5 |