title: Exposure to tobacco on the internet: content analysis of adolescents' internet use.
abstract: OBJECTIVE
  We performed a content analysis of all Web pages viewed by a random sample of adolescents to describe exposure to tobacco- and smoking-related text and images.
  
  
  METHODS
  Adolescents (14-17 years of age) with home Internet access were recruited. Internet-tracking software was installed on home computers used by 346 eligible consenting participants. All Web pages viewed by adolescent participants were captured during a 30-day period for each subject. Keywords on smoking and tobacco were used to identify tobacco images or text.
  
  
  RESULTS
  The 346 participants viewed 1.2 million Web pages, of which 8702 (0.72%) contained tobacco or smoking content. Exposure to tobacco content did not vary according to smoking status. Content was protobacco on 1916 pages, antitobacco on 1572, and complex or unclear on 5055. Social networking sites, mainly MySpace, represented 53% of pages (n = 4612) on which tobacco content was found. All pages with smoking content contained references in text, and 256 (3%) contained images. Many (43%) of the adolescents were exposed to protobacco imagery (median: 3 pages per month). Cigarettes were mentioned on 20% of pages. Tobacco products were sold on 50 pages, and 242 pages contained links to tobacco products sold on other pages. On social networking sites, 4121 pages included a mention of smoking status in the authors' individual profiles, with 23% of authors identifying themselves as smokers.
  
  
  CONCLUSIONS
  Many adolescents are consistently exposed to tobacco content on the Internet, but the volume of exposure is limited and not all content represents protobacco content.
authors.affiliation: Julius B. Richmond Center of Excellence, American Academy of Pediatrics, Elk Grove Village, Illinois, USA.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Jenssen
authors.forename: Jonathan D
authors.initials: JD
authors.lastname: Klein
authors.forename: Laura F
authors.initials: LF
authors.lastname: Salazar
authors.forename: Nichole A
authors.initials: NA
authors.lastname: Daluga
authors.forename: Ralph J
authors.initials: RJ
authors.lastname: DiClemente
mesh_terms: D000293:Adolescent; D000329:Advertising / Q000706:statistics & numerical data*; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D020407:Internet / Q000706:statistics & numerical data*; D008297:Male; D012907:Smoking / Q000453:epidemiology*; D000074606:Smoking Prevention; D012932:Social Facilitation; D014481:United States