Table 4 Summary of Risk of bias assessment
| Author/Date | Risk of study participation bias | Risk of Outcome of Measurement bias |
|---|---|---|
| Abdulraheem, I. et al., 2016 [32, 48] | Low | Low |
| Aditya, S. et al. 2013 [34] | High | High |
| Albawani, S.et al., 2016 [41] | Low | Low |
| Bilal, M. et al.,2016 [30] | Low | Low |
| Ramay, B. et al., 2015 [48] | Low | Low |
| Ramay, B. et al., 2016 [31] | Low | Low |
| Israel, E. et al., 2015 [42, 49] | Low | Low |
| Senadheera, G. et al., 2017 | High | Moderate |
| Sah, A. et al. 2016 [50] | High | High |
| Shah, S. et al., 2014 [46] | Moderate | Moderate |
| Shiavong, A. et al., 2017 [51] | Low | Low |