Pulley 2002.

Methods	Country: USA Setting: recruited from postpartum units, intervention involved home visits Quasi‐experimental RCT
Participants	Postpartum mothers who smoke and breastfeed infants
Interventions	Intervention: educational intervention regarding "smoking hygiene" to reduce ETS exposure of infant. Education was delivered by a nurse, and participants were given an educational pamphlet. Air purifiers were provided. Control: data collection only
Outcomes	Mothers completed a smoking habits questionnaire at baseline and at completion of the follow‐up period, 3 weeks later. Frequency of respiratory symptoms in the infant and hospitalisation were recorded at baseline and 3 weeks later.
Type of intervention	Well‐child (peripartum)
Notes	8/29 dropped out after enrolment. Follow‐up period was 3 weeks.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No information provided
Allocation concealment (selection bias)	Unclear risk	No information provided
Incomplete outcome data (attrition bias) All outcomes	High risk	Eight dropped out (25%), 4 from each arm ‐ very high attrition ‐ left 12 in intervention group and 9 in control group. No ITT performed
Blinding of outcome assessment (detection bias) All outcomes	High risk	Data collector aware to which group participants were assigned
Other bias	High risk	Significant difference in numbers of cigarettes smoked during pregnancy between intervention (significantly higher) and control groups ‐ P = 0.26. No ITT analysis. Very small study