Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "The random sequence was generated online from the web site www.randomizer. org"
Allocation concealment (selection bias)	Low risk	Quote: "Each stratum had permuted, even‐numbered, randomly varying block sizes"
Blinding of participants and personnel (performance bias)	Low risk	Quote: "The investigators, supervisors, caregivers, laboratory personnel, and statistician were blinded to the intervention"
Blinding of outcome assessment (detection bias)	Low risk	Quote: "The investigators, supervisors, caregivers, laboratory personnel, and statistician were blinded to the intervention"
Incomplete outcome data (attrition bias)	Low risk	Minimal loss to follow up
Selective reporting (reporting bias)	Low risk	Authors seem to report all the relevant outcomes
Other bias	Low risk	No other risk of bias was noted