title: [Smoking patterns among boys and girls in Danish elementary school classes].
abstract: BACKGROUND
  The objective was to study the correlation between male and female smoking prevalence in elementary school classes at grade nine through group-level analysis.
  
  
  METHODS
  Data was collected by the 1998 Danish contribution to the cross-national study Health Behaviour in School-Aged Children. A standardised questionnaire was applied. This study included ninety school classes at grade nine (1515 students) from a random sample of schools in Denmark. The outcome measure was the proportion of male and female smokers in the school classes.
  
  
  RESULTS
  The proportion of male and female smokers within the school classes did not correlate. For both boys and girls there was a high variation in the proportion of smokers between the school classes.
  
  
  CONCLUSIONS
  The smoking-related social processes that exist in the school classes probably operate in a sex-differentiated manner. The effect of the classroom environment on the students' smoking behaviour must be considered differently for boys and girls.
authors.affiliation: Afdeling for Social Medicin, Institut for Folke-sundhedsvidenskab, Københavns Universitet, Blegdamsvej 3, DK-2200 København N.
authors.forename: Mette
authors.initials: M
authors.lastname: Rasmussen
authors.forename: Mogens T
authors.initials: MT
authors.lastname: Damsgaard
authors.forename: Eva Pernille
authors.initials: EP
authors.lastname: Due
authors.forename: Bjørn E
authors.initials: BE
authors.lastname: Holstein
mesh_terms: D000293:Adolescent; D002648:Child; D003430:Cross-Sectional Studies; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012574:Schools / Q000706:statistics & numerical data*; D017678:Sex Distribution; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology* / Q000523:psychology; D012931:Social Environment; D011795:Surveys and Questionnaires