title: Computer and therapist based brief interventions among cannabis-using adolescents presenting to primary care: one year outcomes.
abstract: OBJECTIVE
  This paper describes outcomes from a randomized controlled trial examining the efficacy of brief interventions delivered by a computer (CBI) or therapist (TBI) among adolescents in urban primary care clinics.
  
  
  METHODS
  Patients (ages 12-18) self-administered a computer survey. Adolescents reporting past year cannabis use completed a baseline survey and were randomized to control, CBI or TBI, with primary (cannabis use, cannabis related consequences - CC) and secondary outcomes [alcohol use, other drug use (illicit and non-medical prescription drugs), and driving under the influence of cannabis (DUI)] assessed at 3, 6, and 12 months.
  
  
  RESULTS
  1416 adolescents were surveyed; 328 reported past year cannabis use and were randomized. Comparisons of the CBI relative to control showed that at 3 months the group by time interaction (G × T) was significant for other drug use and CC, but not for cannabis use, alcohol use, or DUI; at 6 months, the G × T interaction was significant for other drug use but not for cannabis use, alcohol use, or CC. For analyses comparing the TBI to control, at 3 months the G×T interaction was significant for DUI, but not significant for cannabis use, alcohol use, or CC; at 6 months, the G×T interaction was not significant for any variable. No significant intervention effects were observed at 12 months.
  
  
  CONCLUSIONS
  Among adolescent cannabis users presenting to primary care, a CBI decreased cannabis related problems and other drug use and a TBI decreased cannabis DUI in the short-term. Additional boosters may be necessary to enhance these reductions over time.
authors.affiliation: University of Michigan, Department of Psychiatry, Ann Arbor, MI, USA. Electronic address: waltonma@med.umich.edu.
authors.forename: Maureen A
authors.initials: MA
authors.lastname: Walton
authors.forename: Kipling
authors.initials: K
authors.lastname: Bohnert
authors.forename: Stella
authors.initials: S
authors.lastname: Resko
authors.forename: Kristen L
authors.initials: KL
authors.lastname: Barry
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Chermack
authors.forename: Robert A
authors.initials: RA
authors.lastname: Zucker
authors.forename: Marc A
authors.initials: MA
authors.lastname: Zimmerman
authors.forename: Brenda M
authors.initials: BM
authors.lastname: Booth
authors.forename: Frederic C
authors.initials: FC
authors.lastname: Blow
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D002648:Child; D003625:Data Collection / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D002189:Marijuana Abuse / Q000175:diagnosis / Q000523:psychology* / Q000628:therapy*; D011320:Primary Health Care / Q000379:methods*; D013813:Therapy, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome
keywords: Adolescent; Brief intervention; Cannabis; Computer; Primary care