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Assessed Risk of Bias in Evaluated Studies
| Bias | Stephens et al17 | Wei et al16 |
|---|---|---|
| Bias due to confounding | Serious | Serious |
| Bias in selection | Serious | Serious |
| Bias in the classification of interventions | Moderate | Moderate |
| Bias due to deviations from intended interventions | Low | Low |
| Bias due to missing data | Serious | Serious |
| Bias in the measurement of outcomes | Serious | Serious |
| Bias in the selection of the overall result | Serious | Serious |
| Overall bias | Serious | Serious |
