Effect of counselling mothers on their children's exposure to environmental tobacco smoke: randomised controlled trial

Objective To test the efficacy of behavioural counselling for smoking mothe rs in reducing young children's exposure to environmental tobacco smoke, Design Randomised double blind controlled trial, Setting Low income homes in San Diego county, California. Participants 108 ethnically diverse mothers who exposed their children (age d < 4 years) to tobacco smoke in the home. Intervention Mothers were given seven counselling sessions over three month s. Main outcome measures Children's reported exposure to environmental tobacco smoke from mothers in the home and from all sources; children's cotinine c oncentrations in urine. Results Mothers' reports of children's exposure to their smoke in the home declined in the counselled group from 27.30 cigarettes/week at baseline, to 4.47 at three months, to 3.66 at 12 months and in the controls from 24.56, to 12.08, to 8.38. The differences between the groups by time were signifi cant (P = 0.002), Reported exposure to smoke from all sources showed simila r declines, with significant differences between groups by time (P = 0.008) . At 12 months, the reported exposure in the counselled group was 41.2% tha t of controls for mothers' smoke (95% confidence interval 34.2% to 48.3%) a nd was 45.7% (38.4% to 53.0%) that of controls for all sources of smoke. Ch ildren's mean urine cotinine concentrations decreased slightly in the couns elled group from 10.93 ng/ml at baseline to 10.47 ng/ml at 12 months but in creased in the controls from 9.43 ng/ml to 17.47 ng/ml (differences between groups by time P = 0.008). At 12 months the cotinine concentration in the counselled group was 55.6% (48.2% to 63.0%) that of controls. Conclusions Counselling was effective in reducing children's exposure to en vironmental tobacco smoke. Similar counselling in medical and social servic es might protect millions of children from environmental tobacco smoke in t heir homes.