title: Assessing key model parameters for economic evaluation of pandemic influenza interventions: the data source matters.
abstract: BACKGROUND
  In our previous systematic review of economic evaluations of pandemic influenza interventions, five model parameters, namely probability of pandemic, duration of pandemic, severity, attack rate, and intervention efficacy, were not only consistently used in all studies but also considered important by authors.
  
  
  OBJECTIVE
  Because these parameters originated from sources of varying quality ranging from experimental studies to expert opinion, this study aims to analyze the variation in values used according to sources of information across studies.
  
  
  METHODS
  An analysis of estimated values of key parameters for economic modeling was performed against their different data sources, following the standard hierarchy of evidence.
  
  
  RESULTS
  A lack of good-quality evidence to estimate pandemic duration, pandemic probability, and mortality reduction from antiviral treatment results in a large variation of values used in economic evaluations. Although there are variations in quality of evidence used for attack rate, basic reproduction number, and reduction in hospitalizations from antiviral treatment, the estimated values do not vary significantly. The use of higher-quality evidence results in better precision of estimated values compared to lower-quality sources.
  
  
  CONCLUSIONS
  Hierarchies of evidence are a necessary tool to identify appropriate model parameters to populate economic evaluations and should be included in methodological guidelines. Knowledge gaps in some key parameters should be addressed, because if good-quality evidence is available, future economic evaluations will be more reliable. Some gaps may not be fulfilled by research but consensus among experts to ensure consistency in the use of these assumptions.
authors.affiliation: Health Intervention and Technology Assessment Program (HITAP), Ministry of Public Health, Nonthaburi, Thailand.|Department of Disease Control, Ministry of Public Health, Nonthaburi, Thailand.
authors.forename: Naiyana
authors.initials: N
authors.lastname: Praditsitthikorn
authors.affiliation: Health Intervention and Technology Assessment Program (HITAP), Ministry of Public Health, Nonthaburi, Thailand.
authors.forename: Surachai
authors.initials: S
authors.lastname: Kotirum
authors.affiliation: Health Intervention and Technology Assessment Program (HITAP), Ministry of Public Health, Nonthaburi, Thailand.
authors.forename: Adun
authors.initials: A
authors.lastname: Mohara
authors.affiliation: Health Intervention and Technology Assessment Program (HITAP), Ministry of Public Health, Nonthaburi, Thailand.
authors.forename: Kuntika
authors.initials: K
authors.lastname: Dumrongprat
authors.affiliation: Pharmaceutical Consultant, Bangkok, Thailand.
authors.forename: Román Pérez
authors.initials: RP
authors.lastname: Velasco
authors.affiliation: Health Intervention and Technology Assessment Program (HITAP), Ministry of Public Health, Nonthaburi, Thailand.
authors.forename: Yot
authors.initials: Y
authors.lastname: Teerawattananon
mesh_terms: D003140:Communicable Disease Control / Q000191:economics*; D003365:Costs and Cost Analysis / Q000592:standards; D003625:Data Collection; D006801:Humans; D007251:Influenza, Human / Q000191:economics* / Q000453:epidemiology / Q000517:prevention & control*; D015233:Models, Statistical; D058873:Pandemics
keywords: costs and cost analysis; disease outbreaks; economic evaluation models; human influenza; model parameters; review
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