OBJECTIVES: Measuring the QALY benefits of new health interventions is critically dependent on the values of the quality-adjustment index - putting the “Q” in QALYs. For many health-related quality of life indexes, including EQ-5D, there are multiple options when selecting the value set for use in a given application. For the purposes of health technology assessment in England and Wales the National Institute for Health and Clinical Excellence has published guidance that when conducting the appraisal of new health technologies the values of the relevant population should be applied. However, the standard set of values used to derive the EQ-5Dindex were collected from a national UK population survey that included Scottish respondents whose healthcare system is organised and funded separately from the NHS in England and Wales. This paper reworks the original UK survey data and presents a new set of weights for EQ-5D recalibrated using the appropriate population values METHODS: The Measurement and Valuation of Health (MVH) survey methods have been fully described elsewhere. A total of 3395 individuals used ranking, rating and TTO methods to value a subset of 15 EQ-5D health states. A total of 360 of these respondents were citizens of Scotland. RESULTS: Scottish respondents reported similar health status compared to their English counterparts. However Scottish TTO values were systematically higher for 23/26 mild-moderate states and 16/17 states worse than dead were lower than English values. The Scottish data were removed from the MVH dataset and a new OLS regression model was constructed (r2=0.492). 70% of values for EQ-5D health states in the revised model differ by more than 0.05 when compared with the original MVH values currently applied by NICE. The impact of applying these weights varies with the severity of the condition under review. CONCLUSION: The use of existing MVH weights appears contraindicated if English QALYs are required.