Table 2.
Results of the quality assessment using of the Cochrane Collaboration tool (A) and the Newcastle-Ottawa quality assessment scale (B).
| Randomized trials (A) | Quality criteria | Selection bias | Performance bias | Detection bias | Attrition bias | Reporting bias | |||||||||
| Random sequence generation | Allocation concealment | Blinding of participants and personnel | Blinding of outcome assessment | Incomplete outcome data | Selective reporting | ||||||||||
| JamaliMoghadamSiahkali, 2021 (28) | Low risk | Unclear | High risk | High risk | Low risk | Low risk | |||||||||
| Kumari, 2020 (29) | Low risk | Unclear | Unclear | High risk | Low risk | Low risk | |||||||||
| Thomas,2021 (32) | Low risk | Unclear | Unclear | High risk | Low risk | Low risk | |||||||||
| Zhang, 2021 (33) | Low risk | Low risk | Low risk | Low risk | Low risk | Low risk | |||||||||
| Retrospective studies (B) | Quality criteria | Selection | Comparability | Exposure | Total (9) | ||||||||||
| Is case definition adequate? (1) | Representativeness of the cases (1) | Selection of controls (1) | Definition of controls (1) | Comparability on basis of design or analysis (2) | Ascertainment of exposure (1) | Same method of ascertainment for cases and controls (1) | Nonresponse rate (1) | ||||||||
| Gao, 2021 (27) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 | ||||||
| Li, 2021 (30) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 | ||||||
| Suna, 2021 (31) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 | ||||||
| Zhao, 2021 (34) | ★ | ★ | ★ | ★ | ★★ | ★ | ★ | ★ | 9 | ||||||