Risk of bias assessment for randomized controlled trials based on the Cochrane Collaboration tool (7)
| Study | Random sequence generation | Allocation concealment | Blinding of participants and researches | Incomplete outcome data | Selective reporting | Baseline imbalance | Sample size |
|---|---|---|---|---|---|---|---|
| Bowyer et al. (12) | High risk | High risk | Low risk | Low risk | Low risk | Low risk | Not calculated |
| Hall (18) | High risk | High risk | Low risk | Low risk | Low risk | Low risk | Not calculated |