Producing other language versions of the EQ-5D

Abstract

The measurement and valuation of HRQoL is increasingly important as a measure of the impact of disease and the outcomes of treatment from the patient’s point of view. A plethora of questionnaires have been developed to measure HRQoL, and these questionnaires are frequently translated for use in languages other than the original. Questionnaires are adapted for various reasons, sometimes to be able to compare or aggregate results obtained in different countries, and sometimes to provide a measure in a given cultural setting where none existed before. When data are to be compared or aggregated across countries it is especially important to ensure that equivalence between translated versions is assessed (Herdman et al, 1998). This requires close attention to the way in which health status and HRQoL measures are developed and adapted for use in different countries. Ideally, before beginning to adapt a questionnaire the extent to which a questionnaire’s content appropriately reflects local concepts of health and quality of life should also be determined.