TABLE 2.
Summary of methodological quality assessment of included studies
| Study | Random sequence generation | Allocation concealment | Performance bias | Detection bias | Attrition bias | Reporting bias | Other bias | Global rating |
|---|---|---|---|---|---|---|---|---|
| Burgener et al. (2008) | Strong | Unclear | Unclear | Strong | Strong | Strong | Unclear | B |
| Cai and Zhang (2018) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Chan et al. (2016) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Chen and Luan (2017) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Low | B |
| Cheng et al. (2014) | Strong | Low | Low | Low | Strong | Strong | Unclear | B |
| Dechamps et al. (2010) | Strong | Low | Low | Low | Strong | Strong | Unclear | B |
| Fogarty et al. (2016) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Huang et al. (2019) | Strong | Unclear | Unclear | Strong | Strong | Strong | Strong | B |
| Lam et al. (2011) | Strong | Unclear | Unclear | Strong | Strong | Strong | Strong | B |
| Lam et al. (2012) | Strong | Unclear | Unclear | Strong | Strong | Strong | Strong | B |
| Li (2016) | Strong | Unclear | Unclear | Strong | Strong | Strong | Unclear | B |
| Li (2017) | Strong | Strong | Low | Strong | Strong | Strong | Strong | B |
| Lin (2016) | Strong | Low | Unclear | Unclear | Strong | Strong | Unclear | B |
| Lin (2017) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Liu et al. (2015) | Strong | Unclear | Low | Unclear | Strong | Strong | Unclear | B |
| Liu et al. (2018) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Siu and Lee (2018) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Strong | B |
| Sungkarat et al. (2018) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Strong | B |
| Tsai et al. (2013) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Wang et al. (2016) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Unclear | B |
| Xia (2017) | Strong | Strong | Low | Strong | Strong | Strong | Strong | B |
| Xu (2019) | Strong | Strong | Unclear | Strong | Strong | Strong | Unclear | B |
| Young (2018) | Strong | Unclear | Unclear | Strong | Strong | Strong | Unclear | B |
| Young (2018) | Strong | Unclear | Unclear | Strong | Strong | Strong | Unclear | B |
| Zheng et al. (2013) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Strong | B |
| Zhou et al. (2016) | Strong | Unclear | Unclear | Unclear | Strong | Strong | Strong | B |
| Zhu et al. (2015) | Strong | Unclear | Low | Unclear | Strong | Strong | Unclear | B |