Design, analysis and presentation of multinational economic studies: the need for guidance.

Over the last decade, there has been a proliferation in the number of economic evaluations of pharmaceuticals to meet the growing demand for information about the economic benefits of healthcare technologies. The majority of these studies have been commissioned by pharmaceutical companies for the purposes of drawing attention to the resource and quality-of-life aspects of new or existing products. Such information has become important in overcoming a new obstacle, namely the demonstration of cost effectiveness (the so-called 'fourth hurdle'), in addition to the three well-established criteria of quality, tolerability and efficacy. To ensure the maintenance of standards, guidance for economic evaluations has emerged lately in the form of guidelines, regulations, principles, policies and positions. Drummond outlined three purposes of these guidelines, as follows: as a requirement prior to reimbursement, as statements of methodological standards, and as a statement of ethical standards. Such guidelines are designed to assist both the economic analyst and the decision-maker. In laying out the state of the art regarding the methodology of economic evaluation, guidelines assist the analyst in performing high-quality, scientifically valid studies, and assist the decision-maker in properly interpreting and assessing their quality. In response to these growing requirements for cost-effectiveness data globally, it has become increasingly common for economic evaluations to be conducted on an international scale. However, the recommendations in pharmacoeconomics guidelines regarding the manner in which these multinational economic evaluations should be designed, analysed and presented are too limited to be of any real value. This article examines the various issues that must be taken into consideration when conducting multinational studies, and provides a review of the techniques and approaches that have been suggested to date. It concludes with recommendations for potential inclusion in future sets of pharmacoeconomic guidelines.