LAUSR

For many years, the National Institute for Health and Care Excellence (NICE) has recommended use of the EQ-5D-3L (3L) [1] and its value set for the UK [2]. Since 2011, an expanded-level instrument, the EQ-5D-5L (5L), has been available [3] and value sets now exist to support its use, including a value set for England [4, 5]. This poses a challenge for NICE. Should it recommend the 5L rather than the 3L? This is neither a trivial nor merely academic matter: the choice of whether to use the 5L (and English value set) or the 3L (and UK value set) is likely to impact estimates of quality-adjusted life-years (QALYs) and incremental cost-effectiveness ratios (ICERs). The size and direction of that impact will depend on the disease and the nature of the health problems. In general, where technologies improve self-reported health, estimates of QALY gains will often be smaller with the 5L [6]. In contrast, where technologies extend the length of life, estimates of QALY gains will be higher (to varying degrees): each year of additional life is assigned a higher utility. The ultimate impact on health technology assessment (HTA) will depend on whether the differences between the 3L and 5L push ICERs from one side of the cost-effectiveness threshold to the other. Given the implications for NICE’s technology appraisal process, and other decisions informed by EQ-5D data, the Department of Health for England has called for an independent validation of the 5L value set, given its relevance to policy [7]. In 2017, NICE released a ‘position statement’ [8] stating that: The 3L value set continues to be used for reference-case analyses. Where 5L data have been collected, reference-case analyses should calculate utilities by mapping the 5L descriptive system data onto the 3L value set, using the van Hout et al. [9] mapping function. NICE supports sponsors of prospective clinical studies continuing to use the 5L to collect data on quality of life. A further position statement is planned for August 2018, to be informed by evidence from various studies underway. These include studies commissioned by the English Department of Health to investigate the implications for past NICE technology appraisals had the 5L been used, and to collect 3L and 5L data in parallel to further improve functions for mapping from one to the other. Other studies, funded by the EuroQol Group, are also underway, investigating various aspects of the relationship between the 3L and 5L across disease areas. The 3L and its UK value set has occupied a special place in NICE’s technology appraisal process since its inception, therefore any transition will inevitably pose challenges; for example, reconciling potential inconsistencies between past and future decisions. Given that evidence will continue to be submitted using both the 3L and 5L for years to come, if both value sets are able to be used, there is a risk of inconsistency between decisions being made in the future. HTA in other countries may also face similar issues. Given the difficulties with any transition away from the 3L, is there a case for NICE to adopt the 5L as its preferred instrument? Papers in this issue of Pharmacoeconomics, which are cited in this commentary, address that question by investigating comparative performance of the 3L and 5L.