Levene 1990.

Study characteristics
Methods	Cross‐over RCT of prone and supine positions
Participants	Included: 13 infants aged 2 to 11 months with upper respiratory tract infection and nasal discharge and 17 infants with lower respiratory tract infection, or bronchiolitis (as determined clinically by tachypnoea, fever, wheeze, crackles on auscultation) Excluded: infants with SaO2 < 85% in air Setting: UK
Interventions	After settling in each position for 10 minutes, infants remained in each position for 20 minutes All participants studied during quiet sleep
Outcomes	SaO2 continuously measured over 20 minutes
Notes	The study was funded by the North East Thames Regional Health Authority.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not stated
Allocation concealment (selection bias)	Unclear risk	Not stated
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not stated
Incomplete outcome data (attrition bias) All outcomes	High risk	Loss to follow‐up 9/39 infants as they did not go to sleep or woke when moved