Cost utility analyses typically incorporate preferences based upon the mean values for health states generated from a sample of the general population. The main argument for using general population values rests upon the premise that in a publicly funded health care system the main objective of the health care system is a societal one, namely to maximise health subject to equity concerns. Alternatively, it can be argued that patients themselves should be asked to value their own health state given that they have first hand experience of the state being valued. This paper investigates the relationship between patient and general population values within the context of a randomised controlled trial to compare alternative treatments for varicose veins. It was found that patients' own health valuations tended to be higher than those of the general population sample. The results from this study have important implications for economic evaluation. The incremental QALY gain for patients receiving treatment for moderate varicose veins would be almost halved if patients' own values were used to estimate QALYs in contrast to the general population values. The results also suggest that the variant of elicitation technique may be more important than the source of those values in revealing discrepancies.