There are several methodological and practical issues surrounding the transferability of economic data that are important to address. A review of what national guidelines for economic evaluations say about transferability is important to understand the context in which transferability is currently practiced and discussed. Aim of this editorial is to discuss the results of a study reviewing the positions of various national guidelines in relation to the transferability and generalizability of data and the methods suggested for addressing issues of transferability presented in this issue.

The recommendations on good research practices for dealing with aspects of transferability are filling an important gap. However, in order for the applied science of Pharmacoeconomics and Outcomes Research to make up for its epistemological aim and the aim of providing normative judgments, the methodological foundation of normative judgments has to be given the same importance as the methodological foundation the scientific community is seeking to establish as good research practices.