title: Distal and proximal family predictors of adolescents' smoking initiation and development: a longitudinal latent curve model analysis.
abstract: BACKGROUND
  Studies on adolescent smoking indicate that the smoking behaviours of their parents, siblings and friends are significant micro-level predictors. Parents' socioeconomic status (SES) is an important macro-level predictor. We examined the longitudinal relationships between these predictors and the initiation and development of adolescents' smoking behaviour in Norway.
  
  
  METHODS
  We employed data from The Norwegian Longitudinal Health Behaviour Study (NLHB), in which participants were followed from the age of 13 to 30. We analysed data from the first 5 waves, covering the age span from 13 to 18, with latent curve modeling (LCM).
  
  
  RESULTS
  Smoking rates increased from 3% to 31% from age 13 to age 18. Participants' smoking was strongly associated with their best friends' smoking. Parental SES, parents' smoking and older siblings' smoking predicted adolescents' initial level of smoking. Furthermore, the same variables predicted the development of smoking behaviour from age 13 to 18. Parents' and siblings' smoking behaviours acted as mediators of parents' SES on the smoking habits of adolescents.
  
  
  CONCLUSIONS
  Parents' SES was significantly associated, directly and indirectly, with both smoking initiation and development. Parental and older siblings' smoking behaviours were positively associated with both initiation and development of smoking behaviour in adolescents. There were no significant gender differences in these associations.
authors.affiliation: Uni Health, Uni Research, Christiesgate 12, 5015 Bergen, Norway. tore.tjora@uni.no
authors.forename: Tore
authors.initials: T
authors.lastname: Tjora
authors.forename: Jørn
authors.initials: J
authors.lastname: Hetland
authors.forename: Leif Edvard
authors.initials: LE
authors.lastname: Aarø
authors.forename: Simon
authors.initials: S
authors.lastname: Øverland
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D000328:Adult; D005195:Family Relations; D005260:Female; D005544:Forecasting; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D015233:Models, Statistical; D009664:Norway / Q000453:epidemiology; D012307:Risk Factors; D012907:Smoking / Q000453:epidemiology / Q000523:psychology*; D012923:Social Class; D055815:Young Adult