title: Better efficacy for the osmotic release oral system methylphenidate among poor adherents to immediate-release methylphenidate in the three ADHD subtypes.
abstract: OBJECTIVE
  To determine factors for switching to osmotic release oral system methylphenidate (OROS-MPH) among poor adherents to immediate-release methylphenidate (IR-MPH); and to compare the efficacy of OROS-MPH on the three attention-deficit/hyperactivity disorder (ADHD) subtypes in a multi-site prospective observational study in Taiwan.
  
  
  METHODS
  The sample included 240 children with ADHD, aged 6-16 years, who were poor adherents to IR-MPH, 137 of whom were switched to OROS-MPH. The child psychiatrists diagnosed the Diagnostic Statistical Manual of Mental Disorders (4th edition) ADHD subtypes and assessed the medical history, adherence, side-effects, global ADHD severity, and family/school effectiveness. Parents reported their child's behavioral symptoms.
  
  
  RESULTS
  The determinants for an OROS-MPH switch were higher dosage, shorter treatment and thrice-daily administration of IR-MPH, and more severe inattention symptoms. Hyperactivity and oppositional symptoms were greater in the ADHD combined and hyperactive-impulsive subtypes than the inattentive subtype. Switching to OROS-MPH significantly improved behavioral symptoms and family/school measures, and this was most evident in the ADHD-combined group, followed by the ADHD-inattentive group. Inattention influenced not only academic performance, but also overall classroom behaviors and the parent-child relationship, with the latter two also influenced by oppositional symptoms.
  
  
  CONCLUSIONS
  This study suggests better efficacy for the OROS-MPH among poor adherents to IR-MPH; however, its effectiveness varied across the three ADHD subtypes (ClinicalTrials.gov number NCT00460720).
authors.affiliation: Department of Child Psychiatry, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Wen-Jiun
authors.initials: WJ
authors.lastname: Chou
authors.forename: Miao-Chun
authors.initials: MC
authors.lastname: Chou
authors.forename: Ruu-Fen
authors.initials: RF
authors.lastname: Tzang
authors.forename: Ya-Chen
authors.initials: YC
authors.lastname: Hsu
authors.forename: Susan Shur-Fen
authors.initials: SS
authors.lastname: Gau
authors.forename: Shin-Jaw
authors.initials: SJ
authors.lastname: Chen
authors.forename: Yu-Yu
authors.initials: YY
authors.lastname: Wu
authors.forename: Ya-Fen
authors.initials: YF
authors.lastname: Huang
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Liang
authors.forename: Helen
authors.initials: H
authors.lastname: Cheng