title: Prevalence of smoking in movies as perceived by teenagers longitudinal trends and predictors.
abstract: BACKGROUND
  Smoking in movies is prevalent. However, use of content analysis to describe trends in smoking in movies has provided mixed results and has not tapped what adolescents actually perceive.
  
  
  OBJECTIVE
  To assess the prospective trends in the prevalence of smoking in movies as perceived by teenagers and identify predictors associated with these trends.
  
  
  METHODS
  Using data from the Minnesota Adolescent Community Cohort Study collected during 2000-2006 when participants were aged between 12 and 18 years (N=4735), latent variable growth models were employed to describe the longitudinal trends in the perceived prevalence of smoking in movies using a four-level scale (never to most of the time) measured every 6 months, and examined associations between these trends and demographic, smoking-related attitudinal and socio-environmental predictors. Analysis was conducted in 2009.
  
  
  RESULTS
  At baseline, about 50% of participants reported seeing smoking in movies some of the time, and another 36% reported most of the time. The prevalence of smoking in movies as perceived by teenagers declined over time, and the decline was steeper in those who were aged 14-16 years than those who were younger at baseline (p≤0.05). Despite the decline, teenagers still reported seeing smoking in movies some of the time. Teenagers who reported more close friends who smoked also reported a higher prevalence of smoking in movies at baseline (regression coefficients=0.04-0.18, p<0.01).
  
  
  CONCLUSIONS
  Teenagers' perception of the prevalence of smoking in movies declined over time, which may be attributable to changes made by the movie industry. Despite the decline, teenagers were still exposed to a moderate amount of smoking imagery. Interventions that further reduce teenage exposure to smoking in movies may be needed to have an effect on adolescent smoking.
authors.affiliation: Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, 55454, USA. choix137@umn.edu
authors.forename: Kelvin
authors.initials: K
authors.lastname: Choi
authors.forename: Jean L
authors.initials: JL
authors.lastname: Forster
authors.forename: Darin J
authors.initials: DJ
authors.lastname: Erickson
authors.forename: Deann
authors.initials: D
authors.lastname: Lazovich
authors.forename: Brian G
authors.initials: BG
authors.lastname: Southwell
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008910:Minnesota; D009040:Motion Pictures / Q000706:statistics & numerical data* / Q000639:trends; D010465:Perception; D015995:Prevalence; D011446:Prospective Studies; D012907:Smoking / Q000453:epidemiology*