TESTING THE VALIDITY OF THE EUROQOL AND COMPARING IT WITH THE SF-36 HEALTH SURVEY QUESTIONNAIRE

There is an interest in the consequences of deriving a single index me asure of health for validity and sensitivity. This paper presents the results of testing a recent example of a general health measure design ed to derive a single index, the Euroqol (EQ), and presents a comparis on with a new, influential profile measure, the Short Form 36 (SF-36) Health Survey Instrument. The EQ and an anglicised version of the SF-3 6 health survey, both designed for self-completion, were included in a postal survey of a random sample of 1980 patients from two practice l ists in Sheffield, UK. The response rate for the EQ questionnaire was 83%, and the rate of completion over 95%. Evidence was found for the c onstruct validity of the EQ dimension responses and the derived total EQ health score in terms of distinguishing between groups with expecte d health differences. Considerable agreement was found between EQ resp onses and the total EQ score, and the UK SF-36 profile scores. There w as substantial evidence of EQ being less sensitive at the ceiling (i.e . low levels of perceived ill-health) and throughout the range of heal th states. A recent restructuring of the EQ, may help overcome some of the problems with the physical dimensions by reducing their skewness.