Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Study available as abstract
Allocation concealment (selection bias)	Unclear risk	Study available as abstract
Blinding of participants and personnel (performance bias)	Unclear risk	Study available as abstract
Blinding of outcome assessment (detection bias)	Unclear risk	Study available as abstract
Incomplete outcome data (attrition bias)	Unclear risk	Study available as abstract
Selective reporting (reporting bias)	Unclear risk	Study available as abstract
Other bias	Unclear risk	Study available as abstract