title: Individual change in methylphenidate use in a national sample of children aged 2 to 11 years.
abstract: OBJECTIVE
  To determine methylphenidate use in children aged 2 to 13 years. To provide age- and sex-specific estimates of methylphenidate initiation and cessation during a 2-year period.
  
  
  METHODS
  Data from 2 cycles of a Canadian household survey yielded a sample of over 10 000 children aged 2 to 11 years at Cycle 1 who continued to participate at Cycle 2. We used logit modelling to estimate Cycle 2 methylphenidate use, methylphenidate use over a 2-year period, and methylphenidate initiation and cessation from Cycles 1 to 2.
  
  
  RESULTS
  In 1996 and 1997, methylphenidate use ranged from 0.32% to 6.31% among children aged 4 to 13 years. School-aged boys were more likely than girls to use methylphenidate. Odds were greater for boys aged 6 to 7 years than for boys aged 4 to 5 years; they were also greater for boys aged 10 to 11 years than for boys aged 12 to 13 years. Almost 1% of children used methylphenidate at both data cycles. Odds of Cycle 2 methylphenidate use were 135 times greater for children using methylphenidate at Cycle 1, compared with nonusers. Methylphenidate initiation ranged from 0.20% to 3.34%, and school-aged boys had higher initiation rates than girls. Cessation rates ranged from 18% to78%, and there were no statistically significant differences by age and sex.
  
  
  CONCLUSIONS
  Methylphenidate prevalence findings are consistent with past studies. We found an age-by-sex interaction on methylphenidate use. We also found both continuity and discontinuity in methylphenidate use.
authors.affiliation: Research Unit on Children's Psychosocial Malajustment, University of Montreal, Quebec. eromano@uottawa.ca
authors.forename: Elisa
authors.initials: E
authors.lastname: Romano
authors.forename: Raymond H
authors.initials: RH
authors.lastname: Baillargeon
authors.forename: Isabel
authors.initials: I
authors.lastname: Fortier
authors.forename: Hong-Xing
authors.initials: HX
authors.lastname: Wu
authors.forename: Philippe
authors.initials: P
authors.lastname: Robaey
authors.forename: Mark
authors.initials: M
authors.lastname: Zoccolillo
authors.forename: Richard E
authors.initials: RE
authors.lastname: Tremblay
mesh_terms: D000367:Age Factors; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D002170:Canada; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000009:adverse effects; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D004363:Drug Utilization / Q000706:statistics & numerical data; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D006801:Humans; D016015:Logistic Models; D008297:Male; D008774:Methylphenidate / Q000008:administration & dosage* / Q000009:adverse effects; D011446:Prospective Studies; D012737:Sex Factors
chemical_list: D000697:Central Nervous System Stimulants; D008774:Methylphenidate