| Study | 1. Randomization | 2. Deviations from intervention | 3. Missing outcome data | 4. Measurement of the outcome | 5. Selection of the reported results | Overall risk of bias |
| Li 2021a | Low | Some concernsa | Low | Low | Low | Some concerns |
| Liu 2021 | Low | Low | Low | Some concernsb | Low | Some concerns |
| Liu 2021 | Low | Low | Low | Some concernsc | Low | Some concerns |
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