EQ-5D as a generic measure of health-related quality of life in Israel: reliability, validity and responsiveness

Background: The European Quality of Life 5-Dimensions questionnaire is one of the most commonly used measures of health-related quality of life. Objectives: To present the feasibility, reliability and validity of the Hebrew version of the EQ-5D. Methods: We conducted face-to-face interviews with a representative sample (n=1666) of the Israeli Jewish population. The data collected included demographic and medical information, and self-valuation of health using the EQ-5D descriptive system, Visual Analogue Scale and Time Trade-Off. Construct validity was assessed by assuming that older individuals, those with a greater burden of diseases, and those reporting experience with their own severe illness would have lower EQ-5D indexes, VAS and TTO values. Testretest reliability was assessed in a small sample (n=50) that was reevaluated after a 3 week interval. Results: Test-retest reliability of the EQ-5D and VAS was very high (r ≥ 0.85). Reliability of the TTO was moderate (r = 0.48). There were significant differences in the EQ-5D index, profiles, VAS and TTO between healthy and sick respondents and younger and older respondents, indicating good validity of the instrument. Conclusions: The Hebrew translation of the EQ-5D is a practical, reliable and valid instrument for assessing the health-related quality of life of the general Israeli Jewish population.