OBJECTIVES

There is growing interest in developing measures that move beyond the health focused Quality Adjusted Life Year (QALY). This is because different conditions have different health and non-health related quality of life (QoL) impacts. Therefore the health focus of many instruments may mean that the effectiveness of treatments improving other outcomes and areas of QoL is underestimated. The aims of this study are to carry out a systematic investigation of the relationship between the EQ-5D-5L (that measures health related QoL) and ASCOT (that measures social care related QoL) across a range of health conditions and demographic groups.

METHODS

Data were collected from an online sample of 981 Australians who completed both the EQ-5D-5L and ASCOT and questions about their health. We compared the scores on each measure across a range of conditions including anxiety, depression, asthma, arthritis and pain). We examined which domains of QoL measured by the instruments are most likely to be responded to across the different conditions. This analysis was repeated based on different sample characteristics. A number of psychometric methods were used to further test the relationship between the measures. This included assessing convergent validity at the overall score and dimension level using correlation methods.

RESULTS

Results indicate that the relationship between the instruments varies across different health conditions (for example, utility values are more highly correlated, and are more likely to be in a similar range for physical health conditions such as Diabetes than for mental health conditions such as depression).

CONCLUSIONS

The results provide information about the areas in which one or other instrument is more likely to be sensitive, compared with areas where there is high agreement between the instruments. This will support the development of measures moving beyond the health focused QALY that are sensitive to the impacts of all conditions.