title: Smoking initiation and cessation in Norway and the United States: a comparison of two cross-sectional surveys.
abstract: OBJECTIVE
  Smoking prevalence in a population is affected by the proportion of adolescents who start to smoke, and the proportion of smokers who quit. Smoking prevalence has declined linearly in the US and in the state of California during the last 2 decades. Due to an increase in female smoking, the Norwegian smoking prevalence has been stable at around 35% since 1980, while other European countries have seen reductions of at least 10 percentage points.
  
  
  METHODS
  We compared data from two cross-sectional studies; one from Western and Central Norway (n = 5014), and one from Northern California (Stanford Five-City Project) (n = 2189).
  
  
  RESULTS
  Norwegian smoking prevalence figures were significantly higher in all age-sex groups younger than 60 years. The proportion of former smokers was not different, suggesting that the differences between the samples are due to higher smoking initiation in Norway. University education was the most potent covariate of both ever-smoking and current smoking across samples and gender. Amount of physical exercise was associated with never-smoking in Norway, but not in the US. Having smoking parents was related to ever-smoking in women but not in men in both samples. Smoking parents also was related to current smoking in Norway but not in the US.
  
  
  CONCLUSIONS
  Norway should increase efforts to prevent smoking initiation among adolescents, and especially among girls.
authors.affiliation: Norwegian University of Science and Technology, Trondheim, Norway. geir.smedslund@medisin.ntnu.no
authors.forename: G
authors.initials: G
authors.lastname: Smedslund
authors.forename: D K
authors.initials: DK
authors.lastname: Ahn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003431:Cross-Cultural Comparison; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway; D012907:Smoking / Q000453:epidemiology*; D016540:Smoking Cessation / Q000706:statistics & numerical data*; D000074606:Smoking Prevention; D014481:United States