Methodological issues and new developments in the economic evaluation of vaccines.

The application of economic evaluation in healthcare, including vaccination programs, has increased exponentially since the 1980s. There are a number of aspects of economic evaluation of vaccine programs that present particular challenges to the analyst. These include the development of the appropriate epidemiological models from which to estimate the costs and benefits; the accurate prediction of uptake rates; the incorporation of quality adjusted survival gains; and the inclusion of intangible but nonetheless important benefits and costs associated with infectious disease and vaccination. The estimation of marginal intervention costs presents specific difficulties, especially for multivalent vaccines and valuing costs and benefits over time is heavily influenced by the choice of discount rate, which is still a controversial topic. Developments in the next 5 years are likely to address all of these issues and result in more sophisticated and accurate models of vaccination programs.