title: A cross-sectional examination of marketing of electronic cigarettes on Twitter.
abstract: BACKGROUND
  Rapid increases in marketing of e-cigarettes coincide with growth in e-cigarette use in recent years; however, little is known about how e-cigarettes are marketed on social media platforms.
  
  
  METHODS
  Keywords were used to collect tweets related to e-cigarettes from the Twitter Firehose between 1 May 2012 and 30 June 2012. Tweets were coded for smoking cessation mentions, as well as health and safety mentions, and were classified as commercial or non-commercial ('organic') tweets using a combination of Naïve Bayes machine learning methods, keyword algorithms and human coding. Metadata associated with each tweet were used to examine the characteristics of accounts tweeting about e-cigarettes.
  
  
  RESULTS
  73,672 tweets related to e-cigarettes were captured in the study period, 90% of which were classified as commercial tweets. Accounts tweeting commercial e-cigarette content were associated with lower Klout scores, a measure of influence. Commercial tweeting was largely driven by a small group of highly active accounts, and 94% of commercial tweets included links to websites, many of which sell or promote e-cigarettes. Approximately 10% of commercial and organic tweets mentioned smoking cessation, and 34% of commercial tweets included mentions of prices or discounts for e-cigarettes.
  
  
  CONCLUSIONS
  Twitter appears to be an important marketing platform for e-cigarettes. Tweets related to e-cigarettes were overwhelmingly commercial, and a substantial proportion mentioned smoking cessation. E-cigarette marketing on Twitter may have public health implications. Continued surveillance of e-cigarette marketing on social media platforms is needed.
authors.affiliation: Institute for Health Research and Policy, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Jidong
authors.initials: J
authors.lastname: Huang
authors.affiliation: Institute for Health Research and Policy, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Rachel
authors.initials: R
authors.lastname: Kornfield
authors.affiliation: Institute for Health Research and Policy, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Glen
authors.initials: G
authors.lastname: Szczypka
authors.affiliation: Institute for Health Research and Policy, University of Illinois at Chicago, Chicago, Illinois, USA.
authors.forename: Sherry L
authors.initials: SL
authors.lastname: Emery
mesh_terms: D000465:Algorithms; D001499:Bayes Theorem; D003132:Commerce; D003430:Cross-Sectional Studies; D066300:Electronic Nicotine Delivery Systems; D004581:Electronics; D006801:Humans; D020407:Internet; D040541:Marketing; D009538:Nicotine / Q000008:administration & dosage; D012907:Smoking; D016540:Smoking Cessation; D061108:Social Media; D062789:Tobacco Products
chemical_list: D009538:Nicotine
keywords: Electronic nicotine delivery devices; Media; Social marketing