Table 2.
Cochrane risk of bias assessment.
| Random sequence generation | Allocation concealment | Performance bias | Detection bias | Attrition bias | Reporting bias | Other sources of bias | Risk of bias | |
|---|---|---|---|---|---|---|---|---|
| Abbas et al. 2016 [33] | + | ? | + | - | + | + | - | HIGH |
| Bahammam 2016 [34] | + | + | + | + | + | + | ? | LOW |
| Charavet et al. 2016 [35] | + | ? | + | + | + | + | - | LOW |
| Ma et al. 2015 [36] | + | ? | + | + | + | + | ? | LOW |
| Alikhani et al. 2013 [37] | + | ? | - | + | + | + | ? | HIGH |
| Al-Naoum et al. 2013 [38] | + | + | + | - | + | + | ? | HIGH |
| Shoreibah et al. 2012 [39] | ? | ? | - | - | + | ? | - | HIGH |
| Shoreibah et al. 2012 [40] | ? | ? | - | - | + | + | - | HIGH |
| Aboul-Ela et al. 2011 [41] | + | ? | + | ? | + | + | ? | HIGH |