A Comparison of PROPr and EQ-5D-5L Value Sets.

objectivesThe EQ-5D-5L and its value sets are widely used internationally. However, in the US and elsewhere, there is growing use of PROMIS, which has a value set (PROPr) based on the stated preferences of the US population. This paper aims to compare the characteristics of EQ-5D-5L and PROPr value sets and to highlight potential implications for users.

methodsUS, Australian and English value sets were used for EQ-5D-5L. PROPr utilities were calculated based on PROMIS-29 + 2. We examined, in each case, (i) the characteristics (e.g. range of values, number of unique values) and distribution of all possible 'theoretical' utilities; (ii) dimension/domain importance ranking by the utility of corner states (i.e. health states with the worst level in one domain and the best in all others); (iii) comparisons of utilities for health states hypothesised to be comparable in terms of severity across EQ-5D-5L descriptive systems and PROMIS-29 + 2 domain scores; (iv) the changes in values of adjacent states (i.e. a one-level change in one dimension for EQ-5D-5L and a four-point change in raw scores for PROMIS-29 + 2, with the other dimensions held constant) for dimensions hypothesised to overlap conceptually or be correlated between the two instruments.

resultsEQ-5D-5L and PROPr utilities differ systematically. First, the US EQ-5D-5L utilities range from - 0.573 to 1, whereas PROPr values for PROMIS-29 + 2 range from - 0.022 to 0.954. Second, in the US (and English) EQ-5D-5L value sets, pain is the most important dimension whereas in PROPr pain is one of the least important (apart from sleep disturbance). Third, classified based on severity across EQ-5D-5L descriptive systems and PROMIS-29 + 2 domain scores, PROPr has substantially lower values than EQ-5D-5L values for comparable 'mild' health states, but higher values for more 'severe' health states. Last, when one dimension is considered across its best to worst levels and all other dimensions are held constant at their best or moderate level, in EQ-5D-5L value sets, the greatest changes in utility occur between levels 3 and 4 (moderate and severe) problems; in PROPr that occurred between the most severe states and their descriptively adjacent health states.

conclusionThere are very considerable differences between US EQ-5D-5L and PROPr utilities, despite both in principle representing utility on the same scale anchored at 0 and 1 and both representing the preferences of the US general public. It is important for decision makers and clinical triallists to be aware of these differences. Further work is needed to assess the impact of these differences in value sets using population and patient data, and in longitudinal settings.