title: Occurence of internet addiction in a general population sample: a latent class analysis.
abstract: BACKGROUND
  Prevalence studies of Internet addiction in the general population are rare. In addition, a lack of approved criteria hampers estimation of its occurrence.
  
  
  OBJECTIVE
  This study conducted a latent class analysis (LCA) in a large general population sample to estimate prevalence.
  
  
  METHODS
  A telephone survey was conducted based on a random digit dialling procedure including landline telephone (n=14,022) and cell phone numbers (n=1,001) in participants aged 14-64. The Compulsive Internet Use Scale (CIUS) served as the basis for a LCA used to look for subgroups representing participants with Internet addiction or at-risk use. CIUS was given to participants reporting to use the Internet for private purposes at least 1 h on a typical weekday or at least 1 h on a day at the weekend (n=8,130).
  
  
  RESULTS
  A 6-class model showed best model fit and included two groups likely to represent Internet addiction and at-risk Internet use. Both groups showed less social participation and the Internet addiction group less general trust in other people. Proportions of probable Internet addiction were 1.0% (CI 0.9-1.2) among the entire sample, 2.4% (CI 1.9-3.1) in the age group 14-24, and 4.0% (CI 2.7-5.7) in the age group 14-16. No difference in estimated proportions between males and females was found. Unemployment (OR 3.13; CI 1.74-5.65) and migration background (OR 3.04; CI 2.12-4.36) were related to Internet addiction.
  
  
  CONCLUSIONS
  This LCA-based study differentiated groups likely to have Internet addiction and at-risk use in the general population and provides characteristics to further define this rather new disorder.
authors.affiliation: Department of Psychiatry and Psychotherapy, University of Lübeck, Research Group S:TEP, Lübeck, Germany.
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Rumpf
authors.forename: Ad A
authors.initials: AA
authors.lastname: Vermulst
authors.forename: Anja
authors.initials: A
authors.lastname: Bischof
authors.forename: Nadin
authors.initials: N
authors.lastname: Kastirke
authors.forename: Diana
authors.initials: D
authors.lastname: Gürtler
authors.forename: Gallus
authors.initials: G
authors.lastname: Bischof
authors.forename: Gert-Jan
authors.initials: GJ
authors.lastname: Meerkerk
authors.forename: Ulrich
authors.initials: U
authors.lastname: John
authors.forename: Christian
authors.initials: C
authors.lastname: Meyer
mesh_terms: D000293:Adolescent; D000328:Adult; D016739:Behavior, Addictive / Q000453:epidemiology*; D004641:Emigration and Immigration / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D020407:Internet; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D015995:Prevalence; D012307:Risk Factors; D014478:Unemployment / Q000706:statistics & numerical data*; D055815:Young Adult