title: Economic Evaluation alongside Multinational Studies: A Systematic Review of Empirical Studies.
abstract: OBJECTIVE
  This study seeks to explore methods for conducting economic evaluations alongside multinational trials by conducting a systematic review of the methods used in practice and the challenges that are typically faced by the researchers who conducted the economic evaluations.
  
  
  METHODS
  A review was conducted for the period 2002 to 2012, with potentially relevant articles identified by searching the Medline, Embase and NHS EED databases. Studies were included if they were full economic evaluations conducted alongside a multinational trial.
  
  
  RESULTS
  A total of 44 studies out of a possible 2667 met the inclusion criteria. Methods used for the analyses varied between studies, indicating a lack of consensus on how economic evaluation alongside multinational studies should be carried out. The most common challenge appeared to be related to addressing differences between countries, which potentially hinders the generalisability and transferability of results. Other challenges reported included inadequate sample sizes and choosing cost-effectiveness thresholds.
  
  
  CONCLUSIONS
  It is recommended that additional guidelines be developed to aid researchers in this area and that these be based on an understanding of the challenges associated with multinational trials and the strengths and limitations of alternative approaches. Guidelines should focus on ensuring that results will aid decision makers in their individual countries.
authors.affiliation: Health Economics Unit, School of Health and Population Sciences, Public Health Building, University of Birmingham, Birmingham, United Kingdom B15 2TT.
authors.forename: Raymond
authors.initials: R
authors.lastname: Oppong
authors.affiliation: Health Economics Unit, School of Health and Population Sciences, Public Health Building, University of Birmingham, Birmingham, United Kingdom B15 2TT.
authors.forename: Sue
authors.initials: S
authors.lastname: Jowett
authors.affiliation: Health Economics Unit, School of Health and Population Sciences, Public Health Building, University of Birmingham, Birmingham, United Kingdom B15 2TT.
authors.forename: Tracy E
authors.initials: TE
authors.lastname: Roberts
mesh_terms: D003362:Cost-Benefit Analysis; D036262:Empirical Research; D006801:Humans; D038622:Internationality