title: Do societal wealth, family affluence and gender account for trends in adolescent cannabis use? A 30 country cross-national study.
abstract: OBJECTIVE
  To examine cross-national changes in frequent adolescent cannabis use (40+ times consumed over life-time at age 15) over time and relate these trends to societal wealth, family affluence and gender.
  
  
  METHODS
  Data from three cycles (2002, 2006, 2010) of the Health Behaviour in School-aged Children (HBSC) Study were used for cross-sectional and trend analyses of adolescent cannabis use.
  
  
  METHODS
  Representative surveys in 30 European and North American countries.
  
  
  METHODS
  A total of 160 606 15-year-old students.
  
  
  METHODS
  Respondents' life-time cannabis use, demographics, family affluence (FAS) and frequency of peer contacts were measured individually. Indicators of wealth (gross domestic product per capita, GDP) and perceived availability of cannabis were obtained from national public data bases.
  
  
  RESULTS
  The frequency of life-time cannabis use decreased over time among adolescents in Europe and North America, particularly in western European countries and the United States (relative risk (RR) = 0.86: confidence interval (CI) 0.79-0.93). This trend was not observed consistently in rapidly developing countries in eastern, central and southern Europe. Over time (2002-10), cannabis use became: (i) less characteristic of high GDP countries in contrast to lower GDP countries (RR = 0.74: CI 0.57-0.95); (ii) less characteristic of youth from high FAS families in contrast to youth from low FAS families (RR = 0.83: CI 0.72-0.96); and (iii) characterized by an increasing gender gap, i.e. consumption was higher among males (RR 1.26: CI 1.04-1.53). Perceived availability of cannabis and peer contacts remained strong predictors of frequent cannabis use.
  
  
  CONCLUSIONS
  Among 30 European and North American countries, cannabis use appears to have 'trickled down' over time, with developing countries taking on the former (heavier) use pattern of richer countries, and less affluent youth taking on the former (heavier) use pattern of more affluent youth. Cannabis use continues to be more common among adolescent males than females.
authors.affiliation: Interdisciplinary Social Sciences, Utrecht University, Utrecht, the Netherlands.
authors.forename: Tom F M
authors.initials: TF
authors.lastname: ter Bogt
authors.forename: Margreet
authors.initials: M
authors.lastname: de Looze
authors.forename: Michal
authors.initials: M
authors.lastname: Molcho
authors.forename: Emmanuelle
authors.initials: E
authors.lastname: Godeau
authors.forename: Anne
authors.initials: A
authors.lastname: Hublet
authors.forename: Anna
authors.initials: A
authors.lastname: Kokkevi
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Kuntsche
authors.forename: Saoirse
authors.initials: S
authors.lastname: Nic Gabhainn
authors.forename: Iva Pejnovic
authors.initials: IP
authors.lastname: Franelic
authors.forename: Bruce
authors.initials: B
authors.lastname: Simons-Morton
authors.forename: Sharon
authors.initials: S
authors.lastname: Sznitman
authors.forename: Alessio
authors.initials: A
authors.lastname: Vieno
authors.forename: Wilma
authors.initials: W
authors.lastname: Vollebergh
authors.forename: William
authors.initials: W
authors.lastname: Pickett
mesh_terms: D000293:Adolescent; D005060:Europe / Q000453:epidemiology; D005260:Female; D059066:Gross Domestic Product; D006801:Humans; D007182:Income; D007398:Interpersonal Relations; D008297:Male; D008385:Marijuana Smoking / Q000191:economics / Q000453:epidemiology / Q000639:trends*; D009656:North America / Q000453:epidemiology; D017678:Sex Distribution; D064890:Social Determinants of Health / Q000706:statistics & numerical data; D012959:Socioeconomic Factors
keywords: Adolescence; cannabis use; family affluence; gender; societal wealth