title: Prioritizing Alcohol Prevention: Establishing Alcohol as the Gateway Drug and Linking Age of First Drink With Illicit Drug Use.
abstract: BACKGROUND
  Given ever-reducing budgets of community and school substance use prevention programs, there is a call for identifying the first substance in the sequence leading to polydrug use.
  
  
  METHODS
  Examining data from a nationally representative sample of 2835 United States 12th graders, we sought to determine (1) the first substance adolescents use; (2) order in which adolescents progress through alcohol, tobacco, and marijuana use; and (3) impact of age of initial substance use on lifetime and frequency of illicit substance use.
  
  
  RESULTS
  Alcohol is the most commonly used substance, and the majority of polysubstance using respondents consumed alcohol prior to tobacco or marijuana initiation. Respondents initiating alcohol use in sixth grade reported significantly greater lifetime illicit substance use (M = 1.9, standard deviation [SD] = 1.7, p < .001) and more frequent illicit substance use (M = 6.0, SD = 6.5, p < .001) than those initiating alcohol use in ninth grade or later. Overall, effect sizes for these differences were large (eta squared = 0.30 and 0.28, respectively).
  
  
  CONCLUSIONS
  Findings underscore the importance of screening for substance use, even among youth enrolled in elementary/middle school. In addition, school prevention programs should begin in elementary school (third grade) and target alcohol use.
authors.affiliation: Department of Health and Kinesiology, Texas A&M University, College Station, TX 77843-4243. aebarry@hlkn.tamu.edu.
authors.forename: Adam E
authors.initials: AE
authors.lastname: Barry
authors.affiliation: Department of Behavioral Science and Community Health, University of Florida, PO Box 100175 HSC, Gainesville, FL 32610-0175. jessking@ufl.edu.
authors.forename: Jessica
authors.initials: J
authors.lastname: King
authors.affiliation: Department of Health Education and Behavior, University of Florida, PO Box 118210, Gainesville, FL 32611-8210. csears@ufl.edu.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Sears
authors.affiliation: Department of Health Education and Behavior, University of Florida, PO Box 118210, Gainesville, FL 32611-8210. charville@hpp.ufl.edu.
authors.forename: Cedric
authors.initials: C
authors.lastname: Harville
authors.affiliation: Department of Health Education and Behavior, University of Florida, PO Box 118210, Gainesville, FL 32611-8210. irinab@ufl.edu.
authors.forename: Irina
authors.initials: I
authors.lastname: Bondoc
authors.affiliation: Department of Health Education and Behavior, University of Florida, PO Box 118210, Gainesville, FL 32611-8210. kjospeh91@ufl.edu.
authors.forename: Kessy
authors.initials: K
authors.lastname: Joseph
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000428:Alcohol Drinking / Q000453:epidemiology / Q000517:prevention & control*; D005260:Female; D006293:Health Promotion; D006801:Humans; D013287:Illicit Drugs; D008297:Male; D008385:Marijuana Smoking / Q000453:epidemiology; D012907:Smoking / Q000453:epidemiology; D019966:Substance-Related Disorders / Q000517:prevention & control; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology
chemical_list: D013287:Illicit Drugs
keywords: adolescents; alcohol; gateway hypothesis; gateway theory; high school; substance use