Exploring differences and similarities of EQ-5D-3L, EQ-5D-5L and WHOQOL-OLD in recipients of aged care services in Germany.

European countries more than ever face shifts towards aging societies with accompanying challenges for health and aged care services. Economic evaluation has mainly relied on health measures such as EQ-5D across populations and conditions. We want to know how well the EQ-5D performs in the target population to avoid bias to the disadvantage of older adults and care-dependents. Therefore, we aim to explore differences and similarities of EQ-5D-3L and EQ-5D-5L in comparison to the old-age specific WHOQOL-OLD instrument in a sample of older adults receiving aged care services. We collected data from n = 329 older adults (≥65 years) receiving aged care services in Germany; the majority was at least 80 years and had varying care needs. We assessed instruments' feasibility, test-retest reliability, instruments' association and sensitivity to known-group differences. In terms of feasibility and test-retest reliability both EQ-5D versions performed better than the WHOQOL-OLD. All measures differentiated well between groups based on aspects of general health and care levels. The analysis of relationship between measures indicated that EQ-5D and WHOQOL-OLD assess partially overlapping, but distinct constructs. We found no clear evidence of superiority of either EQ-5D version over the other. The EQ-5D-5L performed better in terms of test-retest reliability and stronger correlations with WHOQOL-OLD facets. We conclude that using the WHOQOL-OLD alongside EQ-5D in this sample added further information on different aspects of quality of life.

Feasibility and validity of the EQ-5D-3L in the elderly Europeans: a secondary data analysis using SHARE(d) data.

PURPOSE: To determine feasibility and validity of the EQ-5D-3L in the elderly European population. METHODS: Secondary data analysis based on the study of health, ageing, and retirement in Europe (SHARE) to determine the percentage of missing items for EQ-5D dimensions and EQ VAS, and to demonstrate convergent/divergent validity with measures included in the SHARE survey. Known-groups validity was tested using literature-based hypotheses. Correlation coefficients and Cohen's f are reported. RESULTS: Missing values were below 3% across all EQ-5D dimensions and gender strata, slightly increasing with age. Individuals' responses to each EQ-5D dimension were related to their ratings of other measures in expected directions. The EQ VAS and all EQ-5D dimensions (except anxiety/depression) moderately to strongly correlated with physical [e.g. number of limitations in activities of daily living (ADL): r = 0.313-0.658] and generic measures [CASP (control, autonomy, self-realization, pleasure)-19 scale, self-perceived health, number of symptoms: r = 0.318-0.622], while anxiety/depression strongly correlated with the EURO-D scale (r = 0.527). Both EQ-5D dimensions and EQ VAS discriminated well between two [or more] groups known to differ [e.g. anxiety/depression discriminated well between persons classified as depressed/not depressed using the EURO-D scale, f = 0.51; self-care differentiated best between individuals without and with 1 + ADL limitations, f = 0.69]. Sociodemographic variables like gender, education, and partner in household were hardly associated with EQ VAS scores (f < 0.25). CONCLUSION: With item non-response of less than 3%, good discriminatory, and construct properties, the EQ-5D-3L showed to be a feasible and valid measure in the elderly Europeans.

Feasibility properties of the EQ-5D-3L and 5L in the general population: evidence from the GP Patient Survey on the impact of age.

BACKGROUND: There is evidence to suggest that the proportion of missing values is slightly higher in the older population resulting in lower completion rates of the EQ-5D. However, existing studies rarely provide a within-sample comparison of feasibility properties across age groups to quantify this difference. Hence, this study examines feasibility properties of the EQ-5D-3L and 5L in the general population and explores the impact of age on the completion of EQ-5D instruments. METHODS: We pool five waves from the English GP Patient Survey, where respondents self-report their health in either EQ-5D-3L or 5L. Descriptive analysis was undertaken to analyse the distribution and proportion of missing values and completion rates stratified by age and EQ-5D version; logistic regression models were specified to quantify the impact of age, gender and potential long-term conditions on the completion of each of the EQ-5D instruments. RESULTS: The total sample comprises ~ 4.36 million observations, of which 2.88 million respondents report their health in 5L and 1.47 million in 3L, respectively. Respondents over 64 years have slightly more missing values in each dimension than younger respondents. The highest share was observed for the oldest age group in the dimension anxiety/depression (3L 9.1% vs. 5L 7.6%), but was otherwise below 5%. Consequently, completion rates (observed and predicted) decreased with older age and at a higher rate after the age of 64; this was more pronounced for the 3L. CONCLUSION: Evidence from our study suggests that both the EQ-5D-3L and 5L have good feasibility properties. In comparison to younger populations there appears to be a higher proportion of respondents with incomplete responses beyond the age of 64 years. Overall, the 5L version compares more favourably in terms of missing values, completion rates as well as with regard to the expected probability of an incomplete descriptive system.

Developing a New Generic Health and Wellbeing Measure: Psychometric Survey Results for the EQ-HWB.

OBJECTIVES: The development of measures such as the EQ-HWB (EQ Health and Wellbeing) requires selection of items. This study explored the psychometric performance of candidate items, testing their validity in patients, social carer users, and carers. METHODS: Article and online surveys that included candidate items (N = 64) were conducted in Argentina, Australia, China, Germany, United Kingdom, and the United States. Psychometric assessment on missing data, response distributions, and known group differences was undertaken. Dimensionality was explored using exploratory and confirmatory factor analysis. Poorly fitting items were identified using information functions, and the function of each response category was assessed using category characteristic curves from item response theory (IRT) models. Differential item functioning was tested across key subgroups. RESULTS: There were 4879 respondents (Argentina = 508, Australia = 514, China = 497, Germany = 502, United Kingdom = 1955, United States = 903). Where missing data were allowed, it was low (UK article survey 2.3%; US survey 0.6%). Most items had responses distributed across all levels. Most items could discriminate between groups with known health conditions with moderate to large effect sizes. Items were less able to discriminate across carers. Factor analysis found positive and negative measurement factors alongside the constructs of interest. For most of the countries apart from China, the confirmatory factor analysis model had good fit with some minor modifications. IRT indicated that most items had well-functioning response categories but there was some evidence of differential item functioning in many items. CONCLUSIONS: Items performed well in classical psychometric testing and IRT. This large 6-country collaboration provided evidence to inform item selection for the EQ-HWB measure.

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

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.

Generation, Selection, and Face Validation of Items for a New Generic Measure of Quality of Life: The EQ-HWB.

OBJECTIVES: This article aims to describe the generation and selection of items (stage 2) and face validation (stage 3) of a large international (multilingual) project to develop a new generic measure, the EQ-HWB (EQ Health and Wellbeing), for use in economic evaluation across health, social care, and public health to estimate quality-adjusted life-years. METHODS: Items from commonly used generic, carer, social care, and mental health quality of life measures were mapped onto domains or subdomains identified from a literature review. Potential terms and items were reviewed and refined to ensure coverage of the construct of the domains/subdomain (stage 2). Input on the potential item pool, response options, and recall period was sought from 3 key stakeholder groups. The pool of candidate items was tested in qualitative interviews with potential future users in an international face validation study (stage 3). RESULTS: Stage 2 resulted in the generation of 687 items. Predetermined selection criteria were applied by the research team resulting in 598 items being dropped, leaving 89 items that were reviewed by key stakeholder groups. Face validation (stage 3) tested 97 draft items and 4 response scales. A total of 47 items were retained and 14 were modified, whereas 3 were added to the candidate pool of items. This resulted in a 64-item set. CONCLUSIONS: This international multiculture, multilingual study with a common methodology identified many items that performed well across all countries. These were taken to the psychometric testing along with modified and new items for the EQ-HWB.

Feasibility of the EQ-5D in the elderly population: a systematic review of the literature.

PURPOSE: The EQ-5D-3L and 5L are widely used generic preference-based instruments, which are psychometrically sound with the general population, but little is known about the instruments' feasibility in the elderly. Therefore, this systematic review summarises the available literature with regard to the feasibility properties of the instruments in the elderly population. METHODS: We conducted a systematic search in PubMed, PsycInfo and EuroQol databases using pre-specified vocabulary and inclusion/exclusion criteria to identify publications until November 2020. Study characteristics and outcomes referring to the feasibility of the EQ-5D-3L and 5L in the elderly were extracted, if all study participants were at least 65+ years. RESULTS: We identified 17 studies reporting feasibility outcomes based on four criteria: missing values, completion rates, completion time and broad qualitative statements referring to the completion. Missing values per dimension ranged from 0 to 10.7%, although being mostly below 7%. The completion rate was around 90% or better, whereas the EQ VAS rating was missing from 2.3 to 25.3% of the respondents. Only two of the included studies examined the EQ-5D-5L; 15 studies reported on the EQ-5D-3L. CONCLUSION: Comparing our findings against the general population from published literature, we find that feasibility outcomes in older age groups are just below that of younger populations. Furthermore, older respondents have a higher propensity of requiring assistance or even an interviewer-based approach. Nonetheless, the reviewed literature indicates that the EQ-5D-3L still has good feasibility properties and, hence, is highly applicable in older respondents. However, further research is needed to explore feasibility properties of the EQ-5D-5L in this population.

EQ-5D-5L reference values for the German general elderly population.

BACKGROUND: Reference values are a helpful tool to facilitate comparisons of sampled values against a specified reference population. The aim is to describe the health profile and to provide visual analogue scale (EQ VAS) and utility reference values for the EQ-5D-5L from a normative sample of the general elderly population (65+) in Germany. METHODS: We analysed a sub-set of data from the German EQ-5D-5L valuation study using self-reported information based on EQ-5D-5L. We examined the share of respondents in each severity level per dimension as well as means, standard deviations (SD) and 95% confidence intervals for the index and EQ VAS values stratified by age groups and gender. Age was categorised in four groups (65-69, 70-74, 75-79 and > 79 years) to facilitate a more detailed examination of age-related health-related quality of life (HRQoL). RESULTS: The average index and EQ VAS scores were 0.84 (SD 0.22) and 73.2 (SD 18.5), respectively. In total, 21.4% reported no problems in all dimensions. With higher age, health problems were reported more frequently, which, in turn, lead to monotonically decreasing index and EQ VAS values. Overall, men reported fewer problems than women and this difference was largest beyond the age of 80. CONCLUSION: HRQoL in the oldest old appears to be less stable and differs from the young elderly. However, the conventional age categorisation of earlier population norms studies seems to mask these differences. Hence, the more detailed provision of EQ-5D-5L reference values for the elderly population seems helpful for future German studies.

Implausible States: Prevalence of EQ-5D-5L States in the General Population and Its Effect on Health State Valuation.

The EQ-5D is made up of health state dimensions and levels, in which some combinations seem less "plausible" than others. If "implausible" states are used in health state valuation exercises, then respondents may have difficulty imagining them, causing measurement error. There is currently no standard solution: some valuation studies exclude such states, whereas others leave them in. This study aims to address 2 gaps in the literature: 1) to propose an evidence-based set of the least prevalent two-way combinations of EQ-5D-5L dimension levels and 2) to quantify the impact of removing perceived implausible states from valuation designs. For the first aim, we use data from 2 waves of the English General Practitioner Patient Survey (n = 1,639,453). For the second aim, we remodel a secondary data set of a Discrete Choice Experiment (DCE) with duration that valued EQ-5D-5L and compare across models that drop observations involving different health states: 1) implausible states as defined in the literature, 2) the least prevalent states identified in stage 1, and 3) randomly select states, alongside 4) a model that does not drop any observations. The results indicate that two-way combinations previously thought to be implausible actually exist among the general population; there are other combinations that are rarer, and removing implausible states from an experimental design of a DCE with duration leads to value sets with potentially different characteristics depending on the criterion of implausible states. We advise against the routine removal of implausible states from health state valuation studies.

A DELPHI study on aspects of study design to overcome knowledge gaps on the burden of disease caused by serogroup B invasive meningococcal disease.

BACKGROUND: Value assessment of vaccination programs against serogroup B invasive meningococcal disease (IMD) is on the agenda of public health authorities. Current evidence on the burden due to IMD is unfit for pinning down the nature and magnitude of the full social and economic costs of IMD for two reasons. First, the concepts and components that need to be studied are not agreed, and second, measures of the concepts that have been studied are weak and inconsistent. Thus, the economic evaluation of the available serogroup B meningococcal (MenB) vaccines is difficult. The aims of this DELPHI study are to: (1) agree on the concepts and components determining the burden of MenB diseases that need to be studied; and (2) seek consensus on appropriate methods and study designs to measure quality of life (QoL) associated with MenB induced long-term sequelae in future studies. METHODS: We designed a DELPHI questionnaire based on the findings of a recent systematic review on the QoL associated with IMD-induced long-term sequelae, and iteratively interviewed a panel of international experts, including physicians, health economists, and patient representatives. Experts were provided with a controlled feedback based on the results of the previous round. RESULTS: Experts reached consensus on all questions after two DELPHI rounds. Major gaps in the literature relate (i) to the classification of sequelae, which allows differentiation of severity levels, (ii) to the choice of QoL measures, and (iii) to appropriate data sources to examine long-term changes and deficits in patients' QoL. CONCLUSIONS: Better conceptualisation of the structure of IMD-specific sequelae and of how their diverse forms of severity might impact the QoL of survivors of IMD as well as their family network and care-providers is needed to generate relevant, reliable and generalisable data on QoL in the future. The results of this DELPHI panel provide useful guidance on how to choose the study design, target population and appropriate QoL measures for future research and hence, help promote the appropriateness and consistency in study methodology and sample characteristics.