Table 1.
Risk of bias critical assessment—Nonrandomized trials
| Bias domain | Study and ratings | ||||
|---|---|---|---|---|---|
| Kieneker et al50 | Mills et al20 | Smyth et al19 | Cook et al13 | Torres et al44 | |
| Sampling | Low | High | Unclear | N/A | Unclear |
| Representativeness | Low | Low | High | Unclear | High |
| Reliability/validity of outcome | Low | Low | High | Low | Unclear |
| Reliability/validity of exposure | Low | Low | High | Low | Low |
| Blinding of outcome assessment | Low | Low | High | High | Low |
| Risk of selective outcome reporting | Low | Low | Low | Low | Low |
| Confounding | Low | Low | Low | Low | High |