Pediatrician interventions and thirdhand smoke beliefs of parents.

Background: Thirdhand smoke is residual tobacco smoke contamination that remains after a cigarette is extinguished. A national study indicates that adults' belief that thirdhand smoke (THS) harms children is associated with strict household no-smoking policies. The question of whether pediatricians can influence THS beliefs has not been assessed.

Purpose: To identify prevalence of THS beliefs and associated factors among smoking parents, and the association of pediatrician intervention on parent belief that THS is harmful to their children.

Methods: Exit interview data were collected from 1980 parents following a pediatric office visit. Parents' level of agreement or disagreement that THS can harm the health of babies and children was assessed. A multivariate logistic regression model was constructed to identify whether pediatricians' actions were independently associated with parental belief that THS can harm the health of babies and children. Data were collected from 2009 to 2011, and analyses were conducted in 2012.

Results: Ninety-one percent of parents believed that THS can harm the health of babies and children. Fathers (AOR=0.59, 95% CI=0.42, 0.84) and parents who smoked more than ten cigarettes per day (AOR=0.63, 95% CI=0.45, 0.88) were less likely to agree with this statement. In contrast, parents who received advice (AOR=1.60, 95% CI=1.04, 2.45) to have a smokefree home or car or to quit smoking and parents who were referred (AOR=3.42, 95% CI=1.18, 9.94) to a "quitline" or other cessation program were more likely to agree that THS can be harmful.

Conclusions: Fathers and heavier smokers were less likely to believe that THS is harmful. However, pediatricians' actions to encourage smoking parents to quit or adopt smokefree home or car policies were associated with parental beliefs that THS harms children.

Trial Registration: This study is registered at NCT00664261.