Comparison of EQ-5D-3L with QLU-C10D in Metastatic Melanoma Using Cost-Utility Analysis.

BACKGROUND

The National Institute for Health and Care Excellence (NICE) prefers the use of the generic EQ-5D instrument to estimate quality-adjusted life years (QALYs), and recommends that condition-specific instruments only be used when EQ-5D data are not available or not appropriate.

OBJECTIVE

This study aimed to compare the utility gain and cost-effectiveness results of using the generic EQ-5D-3L instrument to the condition-specific Quality-of-Life Utility Measure-Core 10 dimensions (QLU-C10D) by applying both sets of values in a published cost-utility analysis (CUA) of immunotherapy for metastatic melanoma.

METHODS

Quality-of-life data were drawn from a clinical study in which both QLQ-C30 and EQ-5D-3L tools were used. The potential influence of the two instruments on cost-effectiveness was assessed using a three-state Markov model. Descriptive statistics and standard health economic outputs were compared between analyses that applied the two different utility measures.

RESULTS

Mean baseline utility values as measured by the QLU-C10D (mean = 0.744, SD = 0.219) were not statistically different (p > 0.05) compared to values derived from EQ-5D-3L (mean = 0.735, SD = 0.239). The two instruments were correlated (Pearson's correlation = 0.74); however, concordance was low (Lin's concordance correlation coefficient < 0.90) at baseline. The model predicted slightly higher QALYs gained when using EQ-5D-3L over QLU-C10D-derived utilities (1.87 vs 1.74, respectively). This resulted in an incremental cost-effectiveness ratio of US$30.5K when using EQ-5D-3L utilities, compared to US$32.7K when using QLU-C10D utilities. Cost-effectiveness acceptability curves based on the two sets of utilities were almost indistinguishable.

CONCLUSION

This study supports the use of the generic EQ-5D instrument in immunotherapy treated metastatic melanoma, and found no additional benefit for using the disease-specific QLU-C10D when using Australian weights.