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Assessment of risk of bias in included studies
| Author, year | Selection (Max=4) | Comparability (Max=2) | Exposure/Outcome) (Max=3) | Overall quality score (Max=9) |
|---|---|---|---|---|
| Azizi A, et al. (2012)[7] | *** | * | * | ***** |
| Ramon-Fluixa C, et al. (1999)[4] | * | * | * | *** |
| Rai NP, et al. (2016)[5] | ** | * | * | **** |
| Wang H, et al. (2014)[8] | ** | - | * | *** |
| Ertugrul AS, et al. (2013)[9] | *** | * | * | **** |
| Liu H, et al. (2021)[10] | *** | * | * | ***** |
| Wang H, et al. (2014)[11] | ** | * | * | **** |
| Ertugrul AS, et al. (2013)[12] | *** | * | * | ***** |
