Table 2 Assessment of the risk of bias
Auhtors | Borzoei et al. 2017 [25] | Borzoei et al. 2018 [10] | Wang et al. 2007 [26] | Wiweko and Susanto 2017 [27] | Salehpour et al. 2015 [28] | Kort et al. 2014 [29] | Hajimonfared nejad et al. 2017 [30] |
|---|---|---|---|---|---|---|---|
Random sequence generation (selection bias) | L | L | L | L | L | L | L |
Allocation concealment (selection bias) | L | L | L | L | L | L | L |
Blinding of participants and personnel (performance bias) | L | L | L | L | L | L | L |
Blinding of outcome assessment (detection bias) | L | M | U | L | L | U | U |
Incomplete outcome data (attrition bias) | L | L | L | U | L | U | U |
Selective reporting (reporting bias) | M | L | U | L | U | L | L |
Other bias | L | L | L | U | U | L | U |
Overall quality | L | L | L | L | L | L | L |