Table 2.
Study quality assessment according to risk of bias tool
| Author (year) | Study design | ROBINS-I | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Bias due to confounding | Bias in selection of participants into the study | Bias in measurement of interventions | Bias due to departures from intended interventions | Bias due to missing data | Bias in measurement of outcomes | Bias in selection of the reported result | Overall bias | ||
| Halliday (1987) | RCT | ||||||||
| Hagstroem (2008) | Retrospective cohort | Serious | Serious | Low | Serious | Moderate | Moderate | Moderate | Serious-critical |
| Hagstroem (2010) | RCT | ||||||||
| Caldwell (2021) | RCT | ||||||||
| ROB-RCT | |||||||||
| Author (year) | Study design | Randomization process | Deviations from intended interventions | Missing outcome data | Measurement of the outcome | Selection of the reported result | Other potential bias | Overall bias | |
| Halliday (1987) | RCT | Some concern | Low concern | Low concern | Low concern | Low concern | Low concern | Some concern | |
| Hagstroem (2008) | Retrospective cohort | ||||||||
| Hagstroem (2010) | RCT | Some concern | Some concern | Low concern | Some concern | Low concern | Some concern | Some concern | |
| Caldwell (2021) | RCT | Low concern | Low concern | Some concern | Low concern | Low concern | Low concern | Some concern | |
RCT: randomized controlled trial.