Newcastle Ottawa Scale Question | First author, year | ||||
---|---|---|---|---|---|
Cheung 2014 [21] | Wang 2018 [22] | Li 2019 [23] | Ou 2019 [24] | Yang 2020 [20] | |
Sampling: Were the subjects in the study representative of the entire population from which they were recruited? | Moderate | Low | Low | High | Low |
Measurement: Incomplete outcome data: attrition bias due to amount, nature or handling of incomplete outcome data | Low | Low | Low | Low | Moderate |
Measurement: Do the analyses adjust for different lengths of follow-up of patients? | Low | Low | Low | Moderate | Low |
Measurement: Selective reporting: reporting bias due to selective outcome reporting | Low | Low | Low | Low | Moderate |
Additional bias: Bias due to problems not covered elsewhere. | Low | Low | Low | Low | Low |