title: Nonmedical drug use among adolescent students: highlights from the 1999 Ontario Student Drug Use Survey.
abstract: BACKGROUND
  During the 1990s, rates of nonmedical drug use among adolescents escalated. We assessed data from 5 cycles of the Ontario Student Drug Use Survey for overall trends in the proportion of students reporting illegal drug use between 1991 and 1999.
  
  
  METHODS
  The survey is a repeated, cross-sectional, 2-stage cluster-design survey of students enrolled in grades 7, 9, 11 and 13. Outcome measures were prevalence of use of 17 drugs, including alcohol and tobacco, over the 12 months preceding the survey.
  
  
  RESULTS
  The rates of drug use increased between 1993 and 1999. The 95% confidence intervals (CIs) for the differences in proportions between 1997 and 1999 indicated significant increases in the overall use of 6 drugs: alcohol (95% CIdiff 6.1, 1.9-10.3), cannabis (95% CIdiff 46.3, 0.2-8.4), glue (95% CIdiff 2.3, 1.3-3.3), other solvents (95% CIdiff 5.0, 3.1-6.3), barbiturates (95% CIdiff 1.9, 0.4-3.4) and hallucinogens such as mescaline and psilocybin (95% CIdiff 3.5, 0.8-6.9). Fewer grade 7 students in 1999 than in earlier cohorts reported using alcohol or cigarettes by age 9.
  
  
  CONCLUSIONS
  The public health implications of the findings are mixed. On the positive side, there is no evidence of increases in early onset of drug use. On the negative side, the overall proportion of students reporting illegal drug use has continued to rise.
authors.affiliation: Centre for Addiction and Mental Health, Toronto, Ont. edward_adlaf@camh.net
authors.forename: E M
authors.initials: EM
authors.lastname: Adlaf
authors.forename: A
authors.initials: A
authors.lastname: Paglia
authors.forename: F J
authors.initials: FJ
authors.lastname: Ivis
authors.forename: A
authors.initials: A
authors.lastname: Ialomiteanu
mesh_terms: D000293:Adolescent; D016000:Cluster Analysis; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D009864:Ontario / Q000453:epidemiology; D011159:Population Surveillance; D015995:Prevalence; D012307:Risk Factors; D013334:Students; D019966:Substance-Related Disorders / Q000453:epidemiology*