| Bias |
Authors' judgement |
Support for judgement |
| Random sequence generation (selection bias) |
Unclear risk |
"randomly assigned", but method of sequence generation not reported |
| Allocation concealment (selection bias) |
Unclear risk |
Not reported |
| Blinding of participants and personnel (performance bias) |
High risk |
Blinding was not possible due to the nature of the intervention |
| Blinding of outcome assessment (detection bias) |
Unclear risk |
Not reported |
| Incomplete outcome data (attrition bias) |
Unclear risk |
Different sample sizes for different outcomes; more participants were analysed at follow‐up than at baseline; and only a sample of participants were included in the analysis. It was unclear whether the researchers were able to collect data from all respondents. |
| Selective reporting (reporting bias) |
Low risk |
All outcomes in the protocol were reported in the published results |
| Other bias |
Low risk |
No other bias identified |
