title: Tobacco use transitions in the United States: The National Longitudinal Study of Adolescent Health.
abstract: OBJECTIVE
  The purpose of this study is to evaluate and describe transitions in cigarette and smokeless tobacco (ST) use, including dual use, prospectively from adolescence into young adulthood.
  
  
  METHODS
  The current study utilizes four waves of the National Longitudinal Study of Adolescent Health (Add Health) to examine patterns of cigarette and ST use (within 30 days of survey) over time among a cohort in the United States beginning in 7th-12th grade (1995) into young adulthood (2008-2009). Transition probabilities were estimated using Markov modeling.
  
  
  RESULTS
  Among the cohort (N=20,774), 48.7% reported using cigarettes, 12.8% reported using ST, and 7.2% reported dual use (cigarettes and ST in the same wave) in at least one wave. In general, the risk for transitioning between cigarettes and ST was higher for males and those who were older. Dual users exhibited a high probability (81%) of continuing dual use over time.
  
  
  CONCLUSIONS
  Findings suggest that adolescents who use multiple tobacco products are likely to continue such use as they move into young adulthood. When addressing tobacco use among adolescents and young adults, multiple forms of tobacco use should be considered.
authors.affiliation: Tobacco Control Research Branch, National Cancer Institute, Rockville, MD, United States. Electronic address: kaufmana@mail.nih.gov.
authors.forename: Annette R
authors.initials: AR
authors.lastname: Kaufman
authors.affiliation: Tobacco Control Research Branch, National Cancer Institute, Rockville, MD, United States.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Land
authors.affiliation: Tobacco Control Research Branch, National Cancer Institute, Rockville, MD, United States.
authors.forename: Mark
authors.initials: M
authors.lastname: Parascandola
authors.affiliation: Tobacco Control Research Branch, National Cancer Institute, Rockville, MD, United States.
authors.forename: Erik
authors.initials: E
authors.lastname: Augustson
authors.affiliation: Center for Tobacco Products, Food and Drug Administration, Silver Spring, MD, United States.
authors.forename: Cathy L
authors.initials: CL
authors.lastname: Backinger
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D015995:Prevalence; D012907:Smoking / Q000453:epidemiology* / Q000639:trends; D014030:Tobacco, Smokeless / Q000009:adverse effects / Q000706:statistics & numerical data*; D014481:United States / Q000453:epidemiology; D055815:Young Adult
keywords: Adolescent; National Longitudinal Study of Adolescent Health; Smokeless; Smoking; Tobacco