BRIEF REPORT Intervention to reduce environmental tobacco smoke exposure in Latino children: null effects on hair biomarkers and parent reports

Objective: To evaluate the effectiveness of a lay delivered intervention to reduce Latino children’s exposure to environmental tobacco smoke (ETS). The a priori hypothesis was that children living in households that were in the intervention group would have lower exposure over time than measurement only controls. Design: A two group, randomised control trial was conducted. Setting: Areas of San Diego county with a large Latino population. Participants: 143 Latino parent–child pairs. Intervention: Trained bicultural and bilingual Latina lay community health advisors, or promotoras, conducted problem solving aimed at lowering the target child’s exposure to ETS in the household. Six home and telephone sessions were delivered by the promotoras over a four month period. Main outcome measures: Outcome measures were collected at baseline, immediately post-intervention, three months postintervention, and 12 months post-intervention. Four outcomes were considered: (1) parent’s paper-and-pencil reports of the child’s past month exposure; (2) hair samples from the child analysed for past month nicotine; (3) hair samples from the child analysed for past month cotinine; and (4) per cent confirmed reducers. Results: There were no significant condition-by-time interactions, the term indicative of a differential intervention effect. Significant or near significant time main effects were seen for children’s hair cotinine, per cent confirmed reducers, and, in particular, parent reports of exposure. Conclusions: Applying a lay promotora model to deliver the behavioural problem solving intervention unfortunately was not effective. A likely explanation relates to the difficulty of delivering a relatively complex intervention by lay women untrained in behaviour change theory and research methods.