Background: Children's exposure to other people's cigarette smoke (environmental tobacco smoke, or ETS) is associated with a range of adverse health outcomes for children. Parental smoking is a common source of children's exposure to ETS. Preventing exposure to cigarette smoke in infancy and childhood has significant potential to improve children's health worldwide.
Objectives: To determine the effectiveness of interventions aiming to reduce exposure of children to ETS.
Search strategy: We searched the Cochrane Tobacco Addiction Group trials register and conducted additional searches of two health and education databases not included in this specialised register. Date of the most recent search: October 2007.
Selection criteria: Interventions tested using controlled trials with or without random allocation were included in this review if the interventions addressed participants (parents and other family members, child care workers and teachers) involved with the care and education of infants and young children (aged 0-12 years). All mechanisms for reduction of children's environmental tobacco smoke exposure, and smoking prevention, cessation, and control programmes were included. These include smoke-free policies and legislation, health promotion, social-behavioural therapies, technology, education and clinical interventions.
Data collection and analysis: Two authors independently assessed studies and extracted data. Due to heterogeneity of methodologies and outcomes, no summary measures were possible and results were synthesised using narrative summaries.
Main results: Thirty-six studies met the inclusion criteria. Four interventions were targeted at populations or community settings, 16 studies were conducted in the 'well child' healthcare setting and 13 in the 'ill child' healthcare setting. Two further studies conducted in paediatric clinics do not make clear whether the visits are to well or ill children, and another includes both well and ill child visits. Nineteen of these studies are from North America and 12 in other high income countries. Five studies are from low- or middle-income countries. In 17 of the 36 studies there was reduction of ETS exposure for children in both intervention and comparison groups. In only 11 of the 36 studies was there a statistically significant intervention effect. Four of these successful studies employed intensive counselling interventions targeted to smoking parents. We found little evidence of difference in effectiveness of interventions between the well infant, child respiratory illness and other child illness settings as contexts for parental smoking cessation interventions. One successful intervention was in the school setting, targeting the ETS exposure of children from smoking fathers.
Authors' conclusions: While brief counselling interventions have been identified as successful ifor adults when delivered by physicians, this cannot be extrapolated to adults as parents in child health settings. However, there is limited support for more intensive counselling interventions for parents in such contexts. There is no clear evidence of differences between the respiratory, non-respiratory ill child, well child and peripartum settings as contexts for reduction of children's ETS exposure.