title: Do provincial policies banning smoking in cars when children are present impact youth exposure to secondhand smoke in cars?
abstract: OBJECTIVE
  To examine youth exposure to smoking in cars following 7 provincial bans on smoking in cars with children in Canada.
  
  
  METHODS
  Repeated cross-sectional data from the 2004-2012 Youth Smoking Survey (n=91,800) were examined. Using a quasi-experimental design, contrasts of the interaction of survey year and province included in the logistic regression analyses were used to test whether exposure significantly declined pre-post implementation of a ban on smoking in cars relative to control provinces not implementing a ban.
  
  
  RESULTS
  Exposure across all provinces declined from 26.5% in 2004 to 18.2% of youth in 2012. Exposure declined significantly from pre to post implementation of a ban on smoking in cars with children in Ontario at time 1 post ban (Pre-Ban=20.4% T1post=10.3%, OR=0.45), time 2 post ban (12.1%, OR=0.61) and time 3 post ban (11.6%, OR=0.58) relative to control provinces that did not implement a ban. In British Columbia exposure to smoking in cars declined significantly at pre-post ban time 3 compared to the control group (Pre-Ban=21.2%, T3post=9.6%, OR=0.51). No other provinces had a significant change in exposure pre-post ban relative to the control provinces.
  
  
  CONCLUSIONS
  Although rates declined, significant differences were only found in Ontario relative to control provinces in the immediate and long term.
authors.affiliation: Department of Social and Epidemiological Research, Centre for Addiction and Mental Health, London, Ontario, Canada; Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada. Electronic address: Tara.EltonMarshall@camh.ca.
authors.forename: Tara
authors.initials: T
authors.lastname: Elton-Marshall
authors.affiliation: School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Scott T
authors.initials: ST
authors.lastname: Leatherdale
authors.affiliation: Department of Psychology, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Pete
authors.initials: P
authors.lastname: Driezen
authors.affiliation: School of Public Health and Health Systems, University of Waterloo, Waterloo, Ontario, Canada; Propel Centre for Population Health Impact, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Sunday
authors.initials: S
authors.lastname: Azagba
authors.affiliation: Propel Centre for Population Health Impact, University of Waterloo, Waterloo, Ontario, Canada.
authors.forename: Robin
authors.initials: R
authors.lastname: Burkhalter
mesh_terms: D000293:Adolescent; D001336:Automobiles; D002170:Canada; D002648:Child; D003430:Cross-Sectional Studies; D006306:Health Surveys; D006801:Humans; D061845:Smoke-Free Policy; D000074606:Smoking Prevention; D014028:Tobacco Smoke Pollution / Q000331:legislation & jurisprudence*
chemical_list: D014028:Tobacco Smoke Pollution
keywords: Children; Policy; Secondhand-smoke; Smoking; Youth