title: Probabilistic Markov Model Estimating Cost Effectiveness of Methylphenidate Osmotic-Release Oral System Versus Immediate-Release Methylphenidate in Children and Adolescents: Which Information is Needed?
abstract: BACKGROUND
  Incidence of attention deficit hyperactivity disorder (ADHD) in children and adolescents has been increasing. The disorder results in high societal costs. Policymakers increasingly use health economic evaluations to inform decisions on competing treatments of ADHD. Yet, health economic evaluations of first-choice medication of ADHD in children and adolescents are scarce and generally do not include broader societal effects.
  
  
  OBJECTIVE
  This study presents a probabilistic model and analysis of methylphenidate osmotic-release oral system (OROS) versus methylphenidate immediate-release (IR). We investigate and include relevant societal aspects in the analysis so as to provide cost-effectiveness estimates based on a broad societal perspective.
  
  
  METHODS
  We enhanced an existing Markov model and determined the cost effectiveness of OROS versus IR for children and adolescents responding suboptimally to treatment with IR. Enhancements included screening of a broad literature base, updated utility values, inclusion of costs and effects on caregivers and a change of the model type from deterministic to probabilistic.
  
  
  RESULTS
  The base case scenario resulted in lower incremental costs (€-5815) of OROS compared with IR and higher incremental quality-adjusted life-year (QALY) gains (0.22). Scenario analyses were performed to determine sensitivity to changes in transition rates, utility of caregivers, medical costs of caregivers and daily medication dose.
  
  
  CONCLUSIONS
  The results indicate that, for children responding suboptimally to treatment with IR, the beneficial effect of OROS on compliance may be worth the additional costs of medication. The presented model adds to the health economic information available for policymakers and to considerations on a broader perspective in cost-effectiveness analyses.
authors.affiliation: Institute for Medical Technology Assessment and Institute of Health Policy and Management, Erasmus University Rotterdam, Rotterdam, The Netherlands, hakkaart@bmg.eur.nl.
authors.forename: Saskia
authors.initials: S
authors.lastname: Schawo
authors.forename: Annemarie
authors.initials: A
authors.lastname: van der Kolk
authors.forename: Clazien
authors.initials: C
authors.lastname: Bouwmans
authors.forename: Lieven
authors.initials: L
authors.lastname: Annemans
authors.forename: Maarten
authors.initials: M
authors.lastname: Postma
authors.forename: Jan
authors.initials: J
authors.lastname: Buitelaar
authors.forename: Michel
authors.initials: M
authors.lastname: van Agthoven
authors.forename: Leona
authors.initials: L
authors.lastname: Hakkaart-van Roijen
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000188:drug therapy* / Q000191:economics; D000697:Central Nervous System Stimulants / Q000008:administration & dosage* / Q000191:economics* / Q000493:pharmacokinetics / Q000627:therapeutic use; D002648:Child; D003362:Cost-Benefit Analysis; D003692:Delayed-Action Preparations / Q000191:economics; D006801:Humans; D008390:Markov Chains; D008774:Methylphenidate / Q000008:administration & dosage* / Q000191:economics* / Q000493:pharmacokinetics / Q000627:therapeutic use; D018803:Models, Economic; D009995:Osmosis; D010349:Patient Compliance; D019057:Quality-Adjusted Life Years; D016896:Treatment Outcome
chemical_list: D000697:Central Nervous System Stimulants; D003692:Delayed-Action Preparations; D008774:Methylphenidate