title: Association of parent and best friend smoking with stage of adolescent tobacco smoking.
abstract: OBJECTIVE
  Compare the effect of parental and best friend smoking across the stages of adolescent smoking, from being a never smoker susceptible to smoking, to being a daily smoker
  
  
  METHODS
  National cross-sectional annual survey (2002-2006 combined) of 157,637 Year 10 students aged 14 and 15 years who answered an anonymous self-administered questionnaire.
  
  
  RESULTS
  The effects of smoking by parents and best friend varied with stage of adolescent tobacco smoking. Attributable risk calculations showed that parental and best friend smoking explained only 6.3% of susceptibility to smoking among never smokers, and 21.7% of non-smoking students who had ever experimented with cigarettes. The attributable risk for parental and best friend smoking progressively increased with smoking frequency, up to 78.7% for daily smoking. The effect of best friend smoking was stronger than parental smoking, although there was a synergistic effect of both variables on the risk of daily smoking.
  
  
  CONCLUSIONS
  Smoking by best friend and parents are strongly associated with current smoking by adolescents, but unrelated to susceptibility to smoke among those who are non-smokers.
authors.affiliation: School of Population Health, University of Auckland, Auckland, New Zealand. r.scragg@auckland.ac.nz
authors.forename: Robert
authors.initials: R
authors.lastname: Scragg
authors.forename: Marewa
authors.initials: M
authors.lastname: Glover
authors.forename: Janine
authors.initials: J
authors.lastname: Paynter
authors.forename: Grace
authors.initials: G
authors.lastname: Wong
authors.forename: Judith
authors.initials: J
authors.lastname: McCool
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009520:New Zealand / Q000453:epidemiology; D010290:Parents; D010379:Peer Group; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology / Q000523:psychology*; D011795:Surveys and Questionnaires