title: Multiple substance use patterns in adolescents-A multilevel latent class analysis.
abstract: BACKGROUND
  Multiple substance use among adolescents is associated with a number of negative consequences. Therefore, we aim to investigate multiple substance use patterns among young adolescents and identify possible multilevel predictors.
  
  
  METHODS
  We analyzed a longitudinal sample of 2490 German students (51% male; Mage=13.32, SD=0.57) at 45 schools in four German states (Bremen, Hesse, North Rhine-Westphalia, Schleswig-Holstein), who completed two assessments in fall, 2010 and fall, 2013. We conducted multilevel latent class analysis for follow-up data on a variety of outcomes, and tested our final 3-class-model for possible baseline predictors. Follow-up substance use measures included lifetime use, current use, and amount of substance for cigarettes and alcohol. Baseline covariates comprised age, gender, socio-economic status, bullying, victimization, peer and parental use, type of school, and health certification of school.
  
  
  RESULTS
  We identified three latent classes: non-users (n=1541; 61.9%), experimenters (n=722; 29.0%), and multiusers (n=227; 9.1%). Experimental consumption was predicted by higher baseline age (OR=1.71; 1.31-2.24), paternal drinking (OR=2.89; 1.23-6.79), and school type (OR=2.57; 1.83-3.61), while multiuse was predicted by peer smoking (OR=2.94; 1.80-4.80) and drinking (OR=2.13; 1.32-3.44), maternal drinking (OR=6.26; 2.02-19.43), bullying (OR=1.69; 1.15-2.48), higher age (OR=1.92; 1.40-2.62), and school type (OR=4.76; 2.75-8.24) compared to the non-users class.
  
  
  CONCLUSIONS
  Prevention and further research on multiple substance use need to concentrate on social influence models and behavior-related interventions, especially at schools without a college-preparatory track.
authors.affiliation: Institute for Therapy and Health Research (IFT-Nord), Harmsstraße 2, Kiel 24114, Germany. Electronic address: tomczyk@ift-nord.de.
authors.forename: Samuel
authors.initials: S
authors.lastname: Tomczyk
authors.affiliation: Institute for Therapy and Health Research (IFT-Nord), Harmsstraße 2, Kiel 24114, Germany.
authors.forename: Reiner
authors.initials: R
authors.lastname: Hanewinkel
authors.affiliation: Institute for Therapy and Health Research (IFT-Nord), Harmsstraße 2, Kiel 24114, Germany.
authors.forename: Barbara
authors.initials: B
authors.lastname: Isensee
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D000367:Age Factors; D000428:Alcohol Drinking / Q000453:epidemiology / Q000523:psychology; D058445:Bullying; D019548:Crime Victims / Q000523:psychology; D005192:Family Health; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008960:Models, Psychological; D055361:Multilevel Analysis; D010379:Peer Group; D012574:Schools; D012907:Smoking / Q000453:epidemiology / Q000523:psychology; D013334:Students / Q000523:psychology; D019966:Substance-Related Disorders / Q000453:epidemiology / Q000517:prevention & control / Q000523:psychology*
keywords: Adolescence; Alcohol; Latent class analysis; Multilevel analysis; Multiple substance use; Smoking