Children Learning About Second-hand Smoking (CLASS): a feasibility cluster randomised controlled trial

Rumana Huque, Omara Dogar, Ian Cameron, Heather Thomson, Amanda Amos, Kamran Siddiqi

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BACKGROUND: Exposure to second-hand smoke is a threat to children's health. We developed a school-based smoke-free intervention (SFI) to support families in implementing smoke-free homes in Bangladesh, and gathered preliminary evidence of its effectiveness.

METHODS: A feasibility cluster randomised controlled trial of SFI was conducted in 24 schools in Mirpur, an urban area within Dhaka. Using simple stratified randomisation, schools were allocated to: Arm A (SFI only), B (SFI plus reminders) and Arm C (the control group). A total of 781 year-five children (10-12 years old) in the consenting schools, participated in the study. Outcomes including 'smoke-free homes' and 'social visibility' i.e. not smoking in front of children at home, were assessed through questionnaire-based children's surveys, administered by researchers, at baseline and at weeks 1, 12, 27 and 52 in all arms.

RESULTS: 'Smoke-free homes' were significantly higher in Arm A (odds ratio (OR) 4.8; 95%CI: 2.6-9.0) and in Arm B (OR 3.9; 95%CI: 2.0-7.5) than in Arm C, when controlled for the baseline levels, at year 1. Similarly, 'social visibility' was significantly reduced in Arm A (OR 5.8; 95% CI: 2.8-11.7) and in Arm B (OR 7.2; 95% CI: 3.3-15.9) than ARM C, when controlled for the baseline levels, at year 1. We observed an increasing trend (Cochrane Armitage test statistic (Z) = 3.8; p <0.0001) in homes becoming smoke-free with increasing intensity of the intervention (Control < Arm A < Arm B), and a decreasing trend (Z = -5.13; p <0.0001) in social visibility at homes.

CONCLUSION: SFI has the potential to encourage children to negotiate a smoke-free environment in their homes.

Original languageEnglish
JournalNicotine & tobacco research
Publication statusPublished - 29 Jan 2015

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