title: Prevalence rates of youths diagnosed with and medicated for ADHD in a nationwide survey in Taiwan from 2000 to 2011.
abstract: Public controversy regarding the potential overdiagnosis and overmedication of children with attention-deficit/hyperactivity disorder (ADHD) has continued for decades. This study used the National Health Insurance Research Database of Taiwan (NHIRD-TW) to explore trends in ADHD diagnosis in youths and the proportion of those receiving medication, with the aim of determining whether ADHD is overdiagnosed and overmedicated in Taiwan.
  
  
  
  Youths (age ≤18 years) who had at least two NHIRD-TW claims records with ADHD diagnosis between January 2000 and December 2011 were selected as the subject cohort. In total, the study sample comprised 145 018 patients with ADHD (mean age at a diagnosis of ADHD: 7.7 ± 3.1 years; 21.4% females). The number of cases of ADHD were calculated annually for each year (from 2000 to 2011), and the number of cases per year who received medication was determined as those with at least one record of pharmacotherapy (immediate-release methylphenidate, osmotic controlled-release formulation of methylphenidate, and atomoxetine) in each year.
  
  
  
  The prevalence rates of a diagnosis of ADHD in the youths ranged from 0.11% in 2000 to 1.24% in 2011. Compared with children under 6 years of age, the ADHD diagnosis rates in children aged between 7 and 12 years (ratio of prevalence rates = 4.36) and in those aged between 13 and 18 years (ratio of prevalence rates = 1.42) were significantly higher during the study period. The prevalence in males was higher than that in females (ratio of prevalence rates = 4.09). Among the youths with ADHD, 50.2% received medications in 2000 compared with 61.0% in 2011. The probability of receiving ADHD medication increased with age. More male ADHD patients received medications that females patients (ratio of prevalence rates = 1.16).
  
  
  
  The rate of ADHD diagnosis was far lower than the prevalence rate (7.5%) identified in a previous community study using face-to-face interviews. Approximately 40-50% of the youths with ADHD did not receive any medications. These findings are not consistent with a systematic public opinion about overdiagnosis or overmedication of ADHD in Taiwan.
authors.affiliation: Department of Child and Adolescent Psychiatry,Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine,Kaohsiung,Taiwan.
authors.forename: L-J
authors.initials: LJ
authors.lastname: Wang
authors.affiliation: Department of Psychiatry,Kaohsiung Veterans General Hospital,Kaohsiung,Taiwan.
authors.forename: S-Y
authors.initials: SY
authors.lastname: Lee
authors.affiliation: Institute of Statistical Science,Academia Sinica,Taipei,Taiwan.
authors.forename: S-S
authors.initials: SS
authors.lastname: Yuan
authors.affiliation: Institute of Biopharmaceutical Sciences,National Yang-Ming University,Taipei,Taiwan.
authors.forename: C-J
authors.initials: CJ
authors.lastname: Yang
authors.affiliation: Genome and Systems Biology Degree Program,National Taiwan University and Academia Sinica,Taipei,Taiwan.
authors.forename: K-C
authors.initials: KC
authors.lastname: Yang
authors.affiliation: Community Medicine Research Center,Keelung Chang Gung Memorial Hospital,Keelung,Taiwan.
authors.forename: T-S
authors.initials: TS
authors.lastname: Huang
authors.affiliation: Department of Child and Adolescent Psychiatry,Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine,Kaohsiung,Taiwan.
authors.forename: W-J
authors.initials: WJ
authors.lastname: Chou
authors.affiliation: Department of Child and Adolescent Psychiatry,Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine,Kaohsiung,Taiwan.
authors.forename: M-C
authors.initials: MC
authors.lastname: Chou
authors.affiliation: Department of Child and Adolescent Psychiatry,Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine,Kaohsiung,Taiwan.
authors.forename: M-J
authors.initials: MJ
authors.lastname: Lee
authors.affiliation: Department of Experimental Radiation Oncology,University of Texas MD Anderson Cancer Center,Houston,Texas,USA.
authors.forename: T-L
authors.initials: TL
authors.lastname: Lee
authors.affiliation: Community Medicine Research Center,Keelung Chang Gung Memorial Hospital,Keelung,Taiwan.
authors.forename: Y-C
authors.initials: YC
authors.lastname: Shyu
mesh_terms: D000293:Adolescent; D018759:Adrenergic Uptake Inhibitors / Q000627:therapeutic use*; D000069445:Atomoxetine Hydrochloride / Q000627:therapeutic use*; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology*; D000697:Central Nervous System Stimulants / Q000627:therapeutic use*; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D000069342:Medical Overuse / Q000706:statistics & numerical data*; D008774:Methylphenidate / Q000627:therapeutic use*; D011159:Population Surveillance; D015995:Prevalence; D013624:Taiwan / Q000453:epidemiology
chemical_list: D018759:Adrenergic Uptake Inhibitors; D000697:Central Nervous System Stimulants; D008774:Methylphenidate; D000069445:Atomoxetine Hydrochloride
keywords: ADHD; diagnosis; epidemiology; pharmacotherapy; prevalence