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The EQ-HWB: Overview of the Development of a Measure of Health and Wellbeing and Key Results

Open AccessPublished:March 08, 2022DOI:https://doi.org/10.1016/j.jval.2022.01.009

      Highlights

      • Measures for estimating quality-adjusted life-years attempt to capture the health of patients but miss broader wellbeing considerations such as autonomy and relationships that are important to patients and care users. Furthermore, they do not consider the impact on carers’ quality of life.
      • This article presents an overview of the international development of a new generic measure, the EQ Health and Wellbeing (EQ-HWB) and a short version of the EQ-HWB using qualitative evidence from service users (health and care services) and carers, along with psychometric evidence, collected in 6 countries.
      • EQ-HWB is designed for evaluating interventions in healthcare, public health, and social care with the intention that it can be used to estimate quality-adjusted life-years to inform decision making both within and between these sectors.

      Abstract

      Objectives

      Existing measures for estimating quality-adjusted life-years are mostly limited to health-related quality of life. This article presents an overview of the development the EQ-HWB (EQ Health and Wellbeing), which is a measure that encompasses health and wellbeing.

      Methods

      Stages: (1) Establishing domains through reviews of the qualitative literature informed by a conceptual framework. (2) Generation and selection of items to cover the domains. (3) Face validation of these items through qualitative interviews with 168 patients, social care users, general population, and carers across 6 countries (Argentina, Australia, China, Germany, United Kingdom, United States). (4) Extensive psychometric testing of candidate items (using classical, factor analysis, and item response theory methods) on > 4000 respondents in the 6 countries. Stakeholders were consulted throughout.

      Results

      A total of 32 subdomains grouped into 7 high-level domains were identified from the qualitative literature and 97 items generated to cover them. Face validation eliminated 36 items, modified 14, and added 3. Psychometric testing of 64 items found little difference in missing data or problems with response distribution, the conceptual model was confirmed except in China, and most items performed well in the item response theory in all countries. Evidence was presented to stakeholders in 2 rounds of consultation to inform the final selection of items for the EQ-HWB (25-item) and the short version of EQ-HWB (9-items).

      Conclusions

      EQ-HWB measures have been developed internationally for evaluating interventions in health, public health, and social care including the impact on patients, social care users, and carers.

      Keywords

      Introduction

      The quality-adjusted life-year (QALY) has become a widely used measure of outcome for use in informing decision making in health technology assessment (HTA).
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      QALYs provide a way to capture benefits in terms of impact on survival and health-related quality of life (HRQOL) valued on a utility scale where one is full health and 0 is equivalent to being dead. Widely used measures for estimating HRQOL on this utility scale are the EQ-5D, SF-6D, and Health Utilities Index Mark 3.
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      These measure an individual’s general health; for example, the EQ-5D describes health across 5 dimensions: mobility, self-care, usual activities, pain or discomfort, and anxiety or depression, with 3 or 5 levels,
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      with an accompanying utility value set usually obtained from the general public.
      The most widely used health measure in economic evaluation, the EQ-5D has been found to be valid in many medical conditions, but performed poorly in others, for example, dementia, multiple sclerosis, severe and complex mental health, and hearing and mixed results in vision.
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      Furthermore, resource allocation decisions are made in related sectors of personal care and other forms of practical support (known in the United Kingdom as social care) and public health, which would benefit from broader utility measures to calculate QALYs. Importantly, the provision of care may not only improve HRQOL but also broader aspects of quality of life (QOL) for the recipients and potentially their carers from better meeting their wants and needs in terms of social care (eg, improved relationships, greater independence, and control). There are also important consequences for the QOL of family or friends who care for them, and increasingly there are interventions designed to support them (eg, respite care).
      Health measures have limited ability in capturing important outcomes in other sectors. Therefore, the Adult Social Care Outcomes Toolkit has been developed for use in social care in England.
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      For the impact on carers, there are measures like CarerQoL-7D, and Adult Social Care Outcomes Toolkit for Carers that have been developed for use in economic evaluation.
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      This proliferation of measures does not allow comparison across sectors. Furthermore, many interventions have impacts across sectors (eg, providing a meal delivery service improves health), but using health and social care outcome measures together risks double counting and using a sector specific measure will miss important outcomes. Developing a common outcome measure, suitable across these sectors, will provide better evidence to strengthen cross-sector decision making.
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      There are number of instruments available that could provide a common measure to be used across sectors. There are subjective wellbeing (SWB) measures, including single self-reported items on happiness and life satisfaction. There are also multi-items measures such as the Warwick-Edinburgh Mental Wellbeing Scale, which contains 14 positively worded items to measure concepts of emotional feelings and psychological flourishing.
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      Currently, these measures do not provide metrics that could be used for estimating QALYs. There has been work to develop monetary valuations of improvements in SWB, but these are not well developed and monetary valuations are not typically used in healthcare.
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      Improving cross-sector comparisons: going beyond the health related QALY.
      Other generic measures that could be used across sectors include the ICEpop Capability Measure (ICECAP) that has been developed to assess a person’s capability in terms of what they “can do” and “able to be” covering aspects related to attachment, stability, achievement, enjoyment, and autonomy.
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      Development of a self-report measure of capability wellbeing for adults: the ICECAP-A.
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      Valuing the ICECAP capability index for older people.
      This is based on Sen’s capabilities framework that is concerned about what a person can do and what they actually achieve in terms of functioning.
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      Welfare and Measurement.
      Both ICECAP for Older People
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      Development of a self-report measure of capability wellbeing for adults: the ICECAP-A.
      and ICECAP for Adults
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      Valuing the ICECAP capability index for older people.
      have preference-based scores estimated form general population values elicited using best-worst scaling. They have not been anchored on the 0 to 1 scale used to estimate QALYs, although they can used in some forms of economic evaluation.
      An important issue is whether decision makers want to rely exclusively on SWB measures, health measures, or some combination. This issue was explored in a qualitative study of the role of wellbeing in resource allocation decisions in health and social care with decision makers in the United Kingdom undertaken in preparation for this research.
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      • Brazier J.E.
      A qualitative study of the views of health and social care decision makers on the role of wellbeing in resource allocation decisions in the UK.
      There was a range of opinions about the role of wellbeing. One broadly held view was that there was a need for improved consideration of broader QOL outcomes. Nevertheless, there was considerable caution in relation to the use of SWB alone because of concerns over interpersonal comparability.
      • Peasgood T.
      • Carlton J.
      • Brazier J.E.
      A qualitative study of the views of health and social care decision makers on the role of wellbeing in resource allocation decisions in the UK.
      Some decision makers, particularly in HTA, wanted to retain the primacy of health to measure benefits. This work influenced the decision to look to develop a measure that combined health and wellbeing domains to enable comparison across sectors.
      For this reason, we embarked on a large, international study to develop a new generic measure of health and wellbeing, the EQ-HWB, that has the potential to estimate QALYs for use across health and social care settings. This article provides a high-level overview of the development of the EQ-HWB. It starts with some background to the study before describing the stages involved, primary results, and how these were used in the development of the EQ-HWB. The reader is provided with references to the accompanying articles in this special issue and elsewhere that provide more in-depth detail.

      Background

      Theoretical Approach

      The theoretical approach underpinning EQ-HWB fits within the extra-welfarist tradition both in aiming for a multidimensional measure of benefit and in using social preferences to judge the value of states.
      • Peasgood T.
      • Mukuria C.
      • Carlton J.
      • et al.
      What is the best approach to adopt for identifying the domains for a new measure of health, social care and carer-related quality of life to measure quality adjusted life years? Application to the development of the EQ-HWB?.
      As Culyer
      • Culyer A.J.
      Commodities, characteristics of commodities, characteristics of people, utilities and quality of life.
      has argued, the “characteristics of people” should be taken into account in addition to utility when evaluating healthcare. The “characteristics of people” includes whether they are happy, pain free, physically mobile, free to choose, and so forth. Furthermore, we wanted a measure that met 3 requirements.
      • Peasgood T.
      • Mukuria C.
      • Carlton J.
      • Connell J.
      • Brazier J.
      Criteria for item selection for a preference-based measure for use in economic evaluation.
      First, the new measure covers aspects of QOL that have been identified as important by service users and their carers. Second, it meets predefined criteria based on being fit for purpose and able to inform resource allocation published in detail elsewhere, including being a single index measure anchored on the 0 (equivalent to dead) to 1 scale (equivalent to full QOL), which reflect social values, have a reasonable degree of confidence in it having interpersonal and intertemporal comparability, are amenable to routine use and clinical trials, and have good measurement properties. The third requirement is that it should be in line with what policy makers in health and social care think is important to their decision making.

      Conceptual Foundation of EQ-HWB

      The development of the EQ-HWB was informed by an initial framework based on the widely known Wilson and Cleary’s
      • Wilson I.B.
      • Cleary P.D.
      Linking clinical variables with HRQoL: a conceptual model of patient outcomes.
      model of HRQOL. This model links biological and physiological variables to symptom status and then to functional health, health perception, and finally QOL. It was modified to include aspects beyond health, with biological functioning extended to include other factors that may have a direct or indirect impact on physical and mental health symptoms, such as being a carer (Fig 1). Impact was extended beyond functioning and activity to include broader aspects of QOL, including control and identity. The Wilson and Cleary
      • Wilson I.B.
      • Cleary P.D.
      Linking clinical variables with HRQoL: a conceptual model of patient outcomes.
      framework was chosen because it provided a simple structure for direct and indirect impacts of circumstances and physiological variables and a useful way of thinking about the connection to environmental and individual mediators, without overimposing model complexity that would be incompatible with our main approach. More detail and rationale for this framework have been published elsewhere.
      • Peasgood T.
      • Mukuria C.
      • Carlton J.
      • et al.
      What is the best approach to adopt for identifying the domains for a new measure of health, social care and carer-related quality of life to measure quality adjusted life years? Application to the development of the EQ-HWB?.
      Figure thumbnail gr1
      Figure 1Conceptual model (adapted from Wilson and Cleary).
      Note: Although there are some dominant causal pathways, there are also many complex bidirectional relationships and interconnections; therefore, arrows are not included in the conceptual model.

      Stakeholder Involvement

      A patient and public involvement and engagement (PPIE) group participated directly in the project throughout the development of the EQ-HWB. This has been detailed elsewhere. The group consisted of 7 members with diversity in sex, ethnicity, and health condition representation across the group. Discussions from each PPIE group session and the outcome of any tasks they undertook were shared with the wider research team and used to help inform decision making.
      There was an online advisory group (n = 124) with members of HTA agencies, broader health and social care commissioners, and academics. Furthermore, members of the National Institute for Health and Care Excellence (NICE) have been a part of the project team (R.L., B.N., and J.C.R.P.) and other NICE staff were invited to provide feedback at different stages of the project. Workshops with members of NICE and the NICE Citizens Council were also held at different stages of the project. Finally, there was project Steering Group (n = 12) made up of academics and stakeholders to oversee the scientific work and the processes of stakeholder engagement and provide feedback throughout the project.

      Overview of the Stages of Developing the EQ-HWB

      The 5 stages of the development the EQ-HWB measures are summarized in Figure 2.
      • Peasgood T.
      • Mukuria C.
      • Carlton J.
      • et al.
      What is the best approach to adopt for identifying the domains for a new measure of health, social care and carer-related quality of life to measure quality adjusted life years? Application to the development of the EQ-HWB?.
      ,

      Mukuria C, Connell J, Carlton J, et al. A targeted review of qualitative evidence on domains of quality of life important for patients, social care users and carers to inform the development of the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      Carlton J, Peasgood T, Mukuria C, et al. Generation, selection and face validation of items for a new generic measure of quality of life, the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      Peasgood T, Mukuria C, Brazier JE, et al. Developing a new generic health and wellbeing measure: psychometric survey results for the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      • Mukuria C.
      • Peasgood T.
      Brazier. Applying EuroQol portable valuation technology to the EQ Health and Wellbeing Short (EQ-HWB-S): a qualitative pilot study [HEDS Discussion paper]. School of Health and Related Research, University of Sheffield.
      Figure thumbnail gr2
      Figure 2Development of the EQ-HWB.
      Note: There were consultations with the PPIE, Advisory and Steering Groups at the end of stages 1, 2, and 3, and for final item selection. References to articles describing each stage made in parentheses. EQ-HWB indicates EQ Health and Wellbeing; EQ-HWB-S, short version of EQ Health and Wellbeing; IRT, item response theory; PPIE, patient and public involvement and engagement; UK, United Kingdom.

      Stage 1: Establishing the Domains

      A review was undertaken of the qualitative literature of the way patients, social care service users, and carers (over the age of 18) report that their conditions, circumstances and related interventions, and impact on their QOL. The methods and results are detailed in a companion article.

      Mukuria C, Connell J, Carlton J, et al. A targeted review of qualitative evidence on domains of quality of life important for patients, social care users and carers to inform the development of the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      The focus was on qualitative research using methods such as interviews and focus groups directly undertaken with them published up to October 2017. The qualitative review included (1) a targeted sample of qualitative reviews in conditions chosen to represent a broad range of physical and mental health problems and (2) qualitative literature concerned with the development or testing of generic measures designed for the evaluation of interventions in health, social care, and carers. Framework analysis and synthesis were undertaken based on the conceptual model (Fig. 1).
      The literature review resulted in 32 subthemes grouped into 7 high-level themes (feelings and emotions, cognition, self-identity, autonomy, relationships, physical sensations, and activity) (Fig. 3). Aspects related to “feelings and emotions,” “activity,” and “relationships and social connections” were recurring themes across the different populations, including those with physical and mental health conditions. These high-level themes were similar although not identical to the initial conceptual framework in Figure 1.
      Figure thumbnail gr3
      Figure 3Preliminary themes and subthemes from the literature review.

      Stage 2: Preliminary Selection of Items

      A comprehensive list of candidate items was generated and categorized into the domains and subdomains from stage 1 (n = 687) as detailed in a companion article.

      Carlton J, Peasgood T, Mukuria C, et al. Generation, selection and face validation of items for a new generic measure of quality of life, the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      There were several iterations of item reduction after group sessions with members of NICE Citizens Council, the PPIE group, and a survey of the advisory group. These groups were given a set of item selection criteria based on existing published criteria
      • Bradburn N.M.
      • Sudman S.
      • Wansink B.
      Asking Questions: The Definitive Guide to Questionnaire Design—For Market Research, Political Polls, and Social and Health Questionnaires.
      ,
      • Streiner D.L.
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      and adapted after consultation with the Steering and Advisory Groups (for details of consultation, see Peasgood et al
      • Peasgood T.
      • Mukuria C.
      • Carlton J.
      • Connell J.
      • Brazier J.
      Criteria for item selection for a preference-based measure for use in economic evaluation.
      ). This stage led to some modification of the domain structure, for example, combining subdomains reflecting control and autonomy, and removal of “burden” as a subdomain. Further modification of items was made after the consultation, and none of the 97 items covering 28 subdomains were taken forward to face validation in their original form.
      A 7-day recall period was chosen for the items based on competing considerations. Asking about today risks missing important events that do not occur every day, such as in episodic conditions like asthma, unless data are collected every day. Furthermore, it is difficult to frame items for subdomains like control, coping, loneliness, and doing the things you want to do around a single 24-hour period. By contrast, a respondent may struggle to remember their experiences over the last month.
      Alternative response choices (including frequency, difficulty, and severity) worked differently across the items, so a selection of response choice options for each item was used in the face validation to get the views of participants.

      Stage 3: Face and Content Validation

      This stage explored the face validity of a set of potential items and is detailed in a companion article.

      Carlton J, Peasgood T, Mukuria C, et al. Generation, selection and face validation of items for a new generic measure of quality of life, the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      Samples were recruited to adequately cover all key interested groups across the 6 countries and to ensure that each proposed item was considered by sufficient sample of people. Each participant saw a subset of the items (approximately 40) from between 2 and 3 domains to avoid excessive burden. For each item, respondents were asked to think about their response to the item, what they thought about when they read the item, and how easy they found it to understand and answer. In some cases, several different response options (such as frequency vs intensity) were presented. This study also examined the cross-cultural relevance of the item content, interpretation of the wording, and translation issues arising from the forward and backward translation of the items into 3 languages of Spanish, German, and Chinese. This information was combined to inform decisions about which items to drop and take forward with or without refinement and response options for the psychometric survey and the final item selection in stage 5.
      There were some common findings across the groups interviewed and the 6 countries. Participants preferred simpler layouts, but they wanted more information on context or definitions to help them complete the items. Participants did not have a clear preference between the positive and negative framing of items or alternative response options, or preferences were expressed without any clear reasons for them. Some items worked well for one group but not as well for another group; for example, being able to look after yourself was an issue for patients but not carers. Participants often forgot or ignored instructions, for example, the recall period.
      These findings resulted 64 items being taken forward (47 with no amendment, 14 with modification, 3 new) covering 26 of the subdomains identified in the literature review and 1 new additional subdomain (self-confidence) and 1 dropped (dignity/respect). Explanations for the decisions are presented in supplemental materials to a companion article.

      Carlton J, Peasgood T, Mukuria C, et al. Generation, selection and face validation of items for a new generic measure of quality of life, the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      Stage 4: Psychometric Study

      The aim of this stage was to examine the domain structure and test the psychometric performance of candidate items. Details are reported in a companion article. Patients, social care users, carers, and members of the general population were recruited in the United Kingdom and in different proportions across the population groups in the 6 countries. Recruitment was online in all countries with an additional article-based sample in the United Kingdom. This resulted in 4830 participants being included in the psychometric analyses across the 6 countries.

      Peasgood T, Mukuria C, Brazier JE, et al. Developing a new generic health and wellbeing measure: psychometric survey results for the EQ Health and Wellbeing (EQ-HWB). Value Health. In press.

      Dimensionality was examined by factor analysis. The conceptual model was reasonably well confirmed, particularly across United Kingdom, Australia, United States, Argentina, and Germany, with some modification in the latter 2 countries, namely, dropping energy and combining mobility and self-care in Germany and combining self-worth and coping in Argentina. There was evidence of high correlation among factors but combining them did not improve overall model fit. The model did not fit the China data as well where many of the feelings subdomains needed to be combined.
      In terms of item performance, there was little difference in rates of missing data across items (ranging from 0.6% to 6.4%). The distribution of responses did not suggest floor or ceiling effects that could not be justified by the prevalence of the condition (eg, poor hearing has a comparatively low prevalence in the general population). Most items were able to distinguish between those with physical and mental health conditions as well as by severity where this was tested. Nevertheless, evidence on known group differences was mixed for carers because the caring role can make health and wellbeing worse (eg, from feeling useful) or worse (eg, feeling tired). Item performance was also assessed using item response theory, which indicated that the response levels of most of the items were ordered, but items functioned differently across some groups. Overall, 32 items worked well, 25 had mixed evidence, and 7 performed poorly. This evidence was taken forward to the next stage.

      Stage 5: Selection of Items for the Measures

      The aim was to ensure that the long version of the EQ-HWB should contain at least 1 item for each of the subdomains, with one or more items where either this would improve the content validity or items provide information at different levels of a latent construct. The short version is limited by the need to be amenable to valuation using standard methods of preference elicitation with members of the general population.
      There were separate rounds of consultation with stakeholders for the long and short versions with the project advisory group, PPIE group, and EuroQol Group membership. To prepare for the consultations, research teams in each of the 6 countries were asked to summarize and combine the face validity and psychometric performance of each item using a summary score on a 4 to 1 scale (ie, item performs very well, fairly well, weakly or mixed evidence, or poorly and why the item is placed in this category, eg, not culturally relevant). Tables 1 and 2 give an example of the scoring items for the relationships domain that was presented to consultees in each round.
      Table 1Summary of FV and psychometric evidence presented in the consultation for the relationships domain.
      In the last 7 days…UKArgentinaAustraliaChinaGermanyUSA
      FVPVOVFVPVOVFVPVOVFVPVOVFVPVOVFVPVOV
      SupportI felt unsupported by other people. (F)343333233433132233
      I had support when I needed it. (F)411432322433323322
      Positive relationsI got along well with people around me. (F)-22333-11-23-11-11
      LonelyI felt lonely. (F)444433344434333333
      I felt there was nobody I was close to. (F)243433132444132243
      I felt I had no one to talk to. (F)433333132344333433
      StigmaI felt people avoided me. (F)232322323433434132
      I felt accepted by others. (F)433433333433423433
      BelongingI felt excluded. (F)444433333444333232
      I felt left out. (F)444444333444444433
      I felt isolated. (F)343222333444232132
      Note. Item performs very well (4), fairly well (3), weakly or mixed evidence (2), and poorly (1).
      F indicates none of the time, only occasionally, some of the time, often, most or all of the time; FV, face validity; OV, overall validity; PV, psychometric validity; UK, United Kingdom; USA, United States of America.
      Table 2Results of consultation for relationships domain.
      Keep inDropUnsurePI groupKeep inDropUnsurePI group
      Unsupported182315DropAvoided53813Unsure
      Support needed222311KeepAccepted261515Unsure
      Lonely4466KeepExcluded172415Keep
      Close to43814DropLeft out251615Unsure
      Talk to202214DropIsolated152714Unsure
      Note. Most participants (n = 53, 93%) agreed to the inclusion of relationships whereas 5% (n = 3) were unsure and 1 participant said no.

      The long version (EQ-HWB)

      The PPIE group was presented with potential items on large, colored cards, with different colors used for each domain. Members were asked to discuss and allocate items to one of 3 categories: include, reject, or undecided. Participants moved around the room placing the items on large boards for each of the categories. After each domain had been considered, members were given the opportunity to reflect upon their decisions, and they had an opportunity to change the allocation of items. The discussion and final allocation of items were noted.
      For the online consultation with the advisory group and EuroQol Group members, a majority of the 59 respondents were from the United Kingdom (59%). Approximately half had an academic background, but the second largest group was those involved in resource allocation decision making (29%). Most respondents indicated they wanted to retain all domains in the long version of the measure. Nevertheless, there was less agreement at the item level when presented with a summary of the evidence on performance of the relevant items for that domain/subdomain. The results for the relationships domain are presented in Tables 1 and 2. Some items clearly stood out, like “loneliness” with 44 consultees wanting to keep it compared with just 6 looking to drop it (Table 2 ). The item about “close to” had 38 indicating it should be dropped. Results were mixed for many items.
      These consultations with the PPIE and the stakeholder groups provided a ranking of the preferences of the consultees for the items, and this was used by the international research team to select the best items to form the 25-item HWB while ensuring there was at least one for each item for each subdomain (see Table 3). For each subdomain, the top-ranking items were reviewed and 1 or 2 items were retained after discussion.
      Table 3EQ-HWB 25 items (items in bold are EQ-HWB-S)—unformatted.
      These questions are trying to measure how your life has been over the last 7 days. Please answer all questions. There are no wrong or right answers.
      Difficulty (no, slight, some, a lot and unable)
       1. How difficult was it for you to see? (using, for example, glasses or contact lenses if you usually use them)
       2. How difficult was it for you to hear? (using, for example, hearing aids if you usually use them)
       3. How difficult was it for you to get around inside and outside? (using, for example, walking stick, frame or wheelchair, if you usually use them)
       4. How difficult was it for you to do day-to-day activities? (for example, working, shopping, housework)
       5. How difficult was it for you to wash, toilet, get dressed, eat or care for your appearance?
      Frequency (none of the time, only occasionally, sometimes, often, most or all the time)
       6. I had problems with my sleep
       7. I felt exhausted
       8. I felt lonely
       9. I felt unsupported by people
       10. I had trouble remembering
       11. I had trouble concentrating/thinking clearly
       12. I felt anxious
       13. I felt unsafe (fear of falling, abuse or other physical harm)
       14. I felt frustrated
       15. I felt sad or depressed
       16. I felt I had nothing to look forward to
       17. I felt I had no control over my day-to-day life (had the choice or do things or have things done for you as you liked and when you wanted)
       18. I felt unable to cope with my day-to-day life
       19. I felt accepted by others (felt like you were able to be yourself and that you belonged)
       20. I felt good about myself
       21. I could do the things I wanted to do
       22. I had physical pain
       23. I had physical discomfort (for example, feeling sick, breathless, itching (not including pain))
       Severity (no, mild, moderate, severe, very severe)
       24. I had physical pain
       25. I had physical discomfort
      © EuroQol Research Foundation. EQ-HWBis a trade mark of the EuroQol Research Foundation
      Note. Questions in bold are EQ-HWB-S.
      EQ-HWB-S indicates short version of EQ Health and Wellbeing.

      Short version (EQ-HWB-S)

      Selection of the subset of items for the short version reflected 2 main concerns. First, the focus should be on “core” generic items relevant for most potential service users. Psychometric evidence around distribution (ceiling and floor effects) and known group validity (by conditions identified across the 6 countries) was considered to help identify subdomains relevant to most respondents. Second, the correlations between the subdomains (latent factors) were considered to identify those subdomains, which could be dropped based on their high correlation with remaining subdomains. Where there was >1 item for a given subdomain in the long version, we also wanted to ensure we selected the best item.
      For this round, the consultation with stakeholders was online with 71 respondents. A majority were from the United Kingdom (54%) and identified as academics (65%). Consultees endorsed and ranked items. They were asked to consider the summary of evidence (eg, Tables 1 and 2) and then to indicate whether they strongly recommended, recommended, or were not sure or do not recommend an item for the short version of EQ-HWB. They were also invited to rank the items and make general comments.
      The international team reviewed the results of this consultation in making their decisions about the final set of items for the draft short version that was sent to the advisory group for comment. The set of items selected for the draft short version included 7 of the 10 most highly ranked items in the consultation. The main exceptions included the personal needs/self-care item, which was difficult to present in a way that was appropriate for all users including carers, and the item “I felt sad/depressed” because there was no other item that covered the full severity range of sadness/depression. The term “depressed” was added even though the stand-alone item “I felt depressed” was not recommended after face validity because of concerns over ambiguity in interpreting this as a clinical diagnosis. The combination with sad addressed that concern, while also ensuring extremely low mood could be picked up. This resulted in the selection of 9 items covering mobility, daily activities, coping, concentration and thinking clearly, anxiety, sad/depression, loneliness, fatigue, and pain.
      Finally, we considered results from the initial qualitative pilot study of the valuation of a sample of states defined by a draft short version using time trade-off (TTO) and discrete choice experiment (DCE) to inform the selection of items for the short version.
      • Mukuria C.
      • Peasgood T.
      Brazier. Applying EuroQol portable valuation technology to the EQ Health and Wellbeing Short (EQ-HWB-S): a qualitative pilot study [HEDS Discussion paper]. School of Health and Related Research, University of Sheffield.
      A convenience sample of 19 individuals in Sheffield (United Kingdom) completed the interview. Before the TTO and DCE tasks, respondents were asked to report their own current state using a draft short version of EQ-HWB (EQ-HWB-S) and 5-level version of EQ-5D (EQ-5D-5L). Participants valued 6 states using TTO (3 EQ-HWB-S and 3 EQ-5D-5L) and 4 EQ-HWB-S states using DCE. After the valuation tasks, they were asked to comment on what they were thinking about when they reported their state using EQ-HWB-S and what was driving their decisions in the TTO and DCE tasks and to compare undertaking the valuation tasks for EQ-HWB states and EQ-5D-5L states.
      The pilot valuation suggested that TTO and DCE are suitable methods to value the draft EQ-HWB-S, although it required more time to deliberate than EQ-5D-5L.
      • Mukuria C.
      • Peasgood T.
      Brazier. Applying EuroQol portable valuation technology to the EQ Health and Wellbeing Short (EQ-HWB-S): a qualitative pilot study [HEDS Discussion paper]. School of Health and Related Research, University of Sheffield.
      The key finding was that the item on coping was problematic because some respondents made their own judgment on whether they could cope with the state described; some found it inconsistent when it was misaligned to depression, anxiety, and exhaustion, and others used it as an overall assessment of all other domains of the state being valued, leading to lexicographic preferences. Nevertheless, coping was clearly important to respondents. It was decided to replace coping with the control item from the long version because this belongs to the same overall domain and they were highly correlated. The pilot also suggested some simplifications to the response choices to aid presentation of states including from “some of the time” to “sometimes.”
      The 9 items selected from the EQ-HWB for the short version are highlighted in Table 3.

      Discussion

      Overall Findings

      This article describes the development of the generic EQ-HWB with 2 versions, EQ-HWB (25 items) and the EQ-HWB-S (9 items), designed for use in economic evaluation of interventions in healthcare, social care, and public health based on the views of service users and their carers. The development process directly engaged service users/patients and carers from inception, with input from stakeholders and policy makers who are interested in the ability of a measure to capture the impact of interventions on both health and wellbeing. The EQ-HWB items cover the themes identified from a review of a large body of qualitative evidence on how health and healthcare, social care, and caring roles impact on health and wellbeing. Items were carefully selected on the bases of evidence from face validation and psychometric testing and the views obtained from consultations with stakeholders, resulting in the 25-item EQ-HWB, with a subset selected for the shorter 9-item EQ-HWB-S. Both versions could be used to generate QALYs once a value set is available, given that the EQ-HWB-S uses items embedded in the EQ-HWB. The long version provides extra domains that may be of interest in some populations.
      The EQ-HWB-S provides an important complement to existing preference-based measures of health like EQ-5D. It covers additional domains such as energy (“I felt exhausted”) and cognition (“I had trouble concentrating/thinking clearly”) that have been recognized as potentially important aspects of health missing from EQ-5D.
      • Finch A.P.
      • Brazier J.E.
      • Mukuria C.
      What is the evidence for the performance of generic preference-based measures? A systematic overview of reviews.
      ,
      • Brazier J.
      • Rowen D.
      • Lloyd A.
      • Karimi M.
      Future directions in valuing benefits for estimating QALYs: is time up for the EQ-5D?.
      In addition, EQ-HWB-S has domains for social relationships (“I felt lonely”) and control found to be important in social care
      • Netten A.
      • Burge P.
      • Malley J.
      • et al.
      Outcomes of social care for adults: developing a preference-weighted measure.
      and for caring.
      • Brouwer W.B.
      • Van Exel N.J.
      • Van Gorp B.
      • Redekop W.K.
      The CarerQol instrument: a new instrument to measure care-related QoL of informal caregivers for use in economic evaluations.
      As reported in this themed issue, a study comparing EQ-5D-5L and EQ-HWB found significant convergence between the measures for overlapping dimensions.

      Monteiro AL, Kuharic M, Pickard AS. Comparison of the newly developed EQ-HWB and the EQ-5D-5L. Value Health. In press.

      Separating out depression and anxiety increased sensitivity. The EQ-HWB also helped to resolve some ceiling effects and a lack of content coverage on the EQ-5D-5L, which suggests that it may have greater validity in certain conditions. Although these additional domains may not be regarded as important for HTA by agencies who want to focus on health, they are highly relevant for healthcare more broadly and social care and for assessing the impact on carers.
      To ensure the measure is amenable to valuation, dimensions have been excluded that are only important for some conditions and circumstances including hearing, vision, sleep, and feeling safe, acceptance, and hope. The longer EQ-HWB version provides a more comprehensive measure that can be used on its own and in future some of these additional items could be examined for valuation. Furthermore, research is being conducted looking at alternative ways to score the longer EQ-HWB using psychometric approaches.
      The strength of the EQ-HWB comes from the broadness of the domains covered, the rigor of its development (combining qualitative and quantitative methods), and being international in its development involving 6 countries covering 4 continents, something not done in the development of previous preference-based measures. Furthermore, there was a wide range of stakeholders informing the content of the new measure, including patients, service users, members of the public, policy makers, and the scientific community, at each stage of development.
      For updates about the EQ-HWB and those interested in using the measure, further information is available at https://euroqol.org/euroqol-is-developing-a-new-instrument-the-eq-hwb-2/.

      Limitations and Future Work

      Despite the size and scale of this international project, there are important limitations. The review was limited to a targeted selection of reviews of common medical conditions because it was not possible to look at all conditions and some rarer conditions may be represented less well by this generic measure.
      Assessment of known group differences was extensive, but there was limited assessment based on severity within groups, and no assessment of change over time, which is an important aspect of the performance of measures; further validation in this context is therefore needed. The groupings used to examine known group validity were very limited for social care users and carers. The psychometric performance requires further testing based on the actual 25- and 9-item versions including studies of equivalence between the direct administration of the EQ-HWB-S and that derived from the same items embedded in the long version. The psychometric analysis included testing in non-English-speaking contexts,

      Augustovski F, Argento F, Rocío R, Luz G, Mukuria C, Belizán M. The development of a new international generic measure (EQ Health and Wellbeing): face validity and psychometric stages in Argentina [published online February 8, 2022]. Value Health. https://doi.org/10.1016/j.jval.2021.12.010.

      but it was not possible to recruit in all groups (eg, long-term conditions, carers) in all 6 countries (except for the United Kingdom). The results from China indicate further validation will be needed to confirm results from the 6 countries in this study in other countries and cultures, including Africa where there has been no work to date.
      The adoption of a 7-day recall period was a pragmatic decision, and it still may be challenging for conditions that result in less frequent episodes. This will be revisited as more is learned about its performance across different conditions and circumstances. There are other aspects of format and presentation that may be modified with further experience. The impact of any further modifications will need to be tested.
      The last stage in the development of the measure is valuation. Although piloting results are promising, a full valuation is required using TTO and DCE for further evidence on the feasibility of valuing a large classification system covering health and wellbeing and whether all the items are important in the context of a valuation study.
      It could be argued that some existing preference-based measures cover important elements of wellbeing. A comparison of health and SWB scales by Richardson et al
      • Richardson J.
      • Iezzi A.
      • Khan M.A.
      • Maxwell A.
      Validity and reliability of the assessment of quality of life (AQoL)-8D multi-attribute utility instrument.
      found that some health utility measures account for a large proportion of variation in SWB, notably Assessment of Quality of Life (AQOL)-8D and SF-6D, whereas EQ-5D accounted for the least. The descriptive systems of AQOL and SF-6D contain some concepts of wellbeing, including affect statements such as “downhearted and low” and “full of life,” and AQOL also covers self-worth, social isolation, and control. Nevertheless, SF-6D misses important domains identified in this research. The AQOL-8D is comprehensive, but with 35 items presents considerable challenges for standard valuation methods and was only developed in 1 country.

      Conclusion

      The EQ-HWB goes beyond the commonly used measures of HRQOL for generating QALYs by encompassing a broader range of generic outcomes including both health and wellbeing. The EQ-HWB is characterized by several important advances: an outcome measure informed by a conceptual framework, designed with extensive input from stakeholders (patients, carers, decision makers involved in HTA), and developed and informed by evidence collected by an international consortium. The EQ-HWB is designed to address the increasing interest in the United Kingdom and elsewhere in integrating health and social care, along with outcomes for carers.

      Article and Author Information

      Author Contributions: Concept and design: Brazier, Peasgood, Mukuria, Pickard, Engel, Carlton, Connell, Rand, Jones, Tsuchiya, Lovett, Monteiro
      Acquisition of data: Peasgood, Mukuria, Marten, Kreimier, Luo, Mulhern, Pickard, Augustovski, Greiner, Engel, Belizan, Yang, Monteiro, Kuharic, Gibbons, Ludwig, Carlton, Connell
      Analysis and interpretation of data: Brazier, Peasgood, Mukuria, Mulhern, Pickard, Augustovski, Engel, Belizan, Yang, Monteiro, Kuharic, Gibbons, Carlton, Connell, Rand, Jones, Monteiro
      Drafting of the manuscript: Brazier, Peasgood, Mukuria, Mulhern, Augustovski, Carlton, Rand, Devlin, Tsuchiya, Monteiro, Rowen
      Critical revision of the paper for important intellectual content: Brazier, Peasgood, Mukuria, Marten, Kreimier, Luo, Mulhern, Pickard, Augustovski, Greiner, Engel, Belizan, Yang, Monteiro, Kuharic, Gibbons, Ludwig, Carlton, Rand, Devlin, Jones, Tsuchiya, Lovett, Rowen, Rejon-Parrilla
      Statistical analysis: Peasgood, Mukuria, Mulhern, Augustovski, Engel, Monteiro, Gibbons, Carlton
      Provision of study materials or patients: Marten, Kreimeier, Augustovski, Greiner, Gibbons, Ludwig
      Obtaining funding: Brazier, Peasgood, Mukuria, Marten, Kreimeier, Luo, Mulhern, Pickard, Greiner, Engel, Yang, Monteiro, Ludwig, Carlton, Devlin, Monteiro
      Administrative, technical, or logistic support: Mukuria, Mulhern, Monteiro, Kuharic, Monteiro, Rejon-Parrilla
      Supervision: Mulhern, Pickard
      Other (Advice from Policy Makers Perspective): Lovett, Rejon-Parrilla
      Conflict of Interest Disclosures: Drs Brazier, Peasgood, Carlton, Connell, Tsuchiya, Lovett, and Rowan reported receiving grants from the EuroQol Research Foundation and the UK Medical Research Council during the conduct of the study. Dr Brazier reported receiving grants and personal fees from the EuroQol Research Foundation outside the submitted work and reported having a patent for the SF-6D and SF-6Dv2 with royalties paid to The University of Sheffield. Drs Brazier, Mukuria, Gibbons, and Carlton reported serving as members of the EuroQol Research Foundation. Dr Mukuria reported receiving grants from the EuroQol Research Foundation during the conduct of the study and reported receiving grants from the EuroQol Research Foundation outside the submitted work. Mr Marten and Drs Kreimeier, Pickard, Greiner, and Ludwig reported receiving grants and nonfinancial support from the EuroQol Research Foundation during the conduct of the study and reported serving as members of the EuroQol Group. Dr Luo reported receiving grants and personal fees from the EuroQol Research Foundation during the conduct of the study and reported receiving grants and personal fees from the EuroQol Research Foundation outside the submitted work. Dr Luo is an editor for Value in Health and had no role in the peer-review process of this article. Dr Mulhern reported receiving grants from the EuroQol Research Foundation during the conduct of the study and reported serving as a member of the EuroQol Research Foundation. Dr Mulhern is an editor for Value in Health and had no role in the peer-review process of this article. Dr Engel reported receiving grants from EuroQol Research Foundation during the conduct of the study and reported serving as a member of the EuroQol Group. Drs Belizan and Yang and Miss Monteiro reported receiving grants from the EuroQol Research Foundation during the conduct of the study. Dr Kuharic reported receiving grants from the EuroQol Research Foundation during the conduct of the study and reported receiving fellowship support for graduate studies from Takeda Pharmaceuticals USA, Inc, during the conduct of this study. Dr Naidoo is employed by the National Institute for Health and Care Excellence. The views expressed in this article are those of the authors and not necessarily of our funders, the National Institute for Health and Care Excellence, the Department of Health and Social Care, or those acknowledged. No other disclosures were reported.
      Funding/Support: This study is an independent research funded by the UK Medical Research Council (grant number 170620) and the EuroQol Research Foundation.
      Role of the Funder/Sponsor: The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.

      Acknowledgment

      The authors thank the National Institute for Health and Care Excellence for highlighting the methodological research need to the Medical Research Council that resulted in the funding call entitled “Beyond the QALY,” which led to this research being funded. The authors acknowledge the support of the National Institute for Health Research Yorkshire and Humber Applied Research Collaboration (formerly CLAHRC) and the National Institute for Health Research Clinical Research Network. The authors acknowledge the invaluable contributions of members of the project Steering Group, advisory group, and patient and public involvement and engagement groups and Julie Johnson for project administration. The authors also thank members of the EuroQol Group Association for their input at plenary and academy meetings and the EuroQol office for their support. Finally, the authors acknowledge the contribution of all the patients, social care users, and informal carers who took part in all the studies across the different countries.

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