Health State Values Research Articles

Public versus patient health preferences: protocol for a study to elicit EQ-5D-5L health state valuations for patients who have survived a stay in intensive care

IntroductionThe value set used when calculating quality-adjusted life-years (QALYs) is most often based on stated preference data elicited from a representative sample of the general population. However, having a severe...

Expect Nothing: The (Lack of) Influence of Subjective Life Expectancy on Valuation of Child Health States.

Earlier research has shown that individuals' subjective life expectancy (SLE) affects health state valuation with time trade-off (TTO). Individuals with longer expected life durations are less willing to trade-off life duration, which yields higher utilities. In this article, the influence of SLE is explored in the valuation of EQ-5D-Y-3L with a proxy perspective, i.e., adults' valuation of health states considering the life of a 10-year-old child. As SLE for children is likely higher, this might explain earlier findings suggesting that individuals are less willing to trade-off years of life for children than for adults. A total of 197 respondents were recruited to take part in digital TTO interviews, facilitated by trained interviewers. TTO interviews were implemented in accordance with the recommended protocol for the valuation of EQ-5D-Y-3L. Respondents valued 10 EQ-5D-Y-3L health states for a 10-year-old child, after which they were asked to report how old they themselves expected to become and also how old they expected a 10-year-old child to become. Generally, adult respondents reported higher SLE for children than for themselves. Neither SLE was systematically associated with the willingness to trade lifetime or the number of life years traded off in TTO tasks. This null-result was substantiated by regression analyses per health state. The results of this study suggest that individuals' expectations about longevity are not associated with EQ-5D-Y-3L valuation. This lack of association is in contrast to earlier work and might be explained by the psychological distance introduced with proxy perspective valuation, or by the methodological differences with earlier work.

Time-Specific Differences in Stated Preferences for Health in the United States.

Changes over time in health state values from a societal perspective may be an important reason to consider updating societal value sets for preference-based measures of health. The aim was to examine whether stated health preferences are different between 2002 and 2017, controlling for demographic changes in the United States. Data from 2002 and 2017 US EQ-5D-3L valuation studies were combined. The primary analysis compared valuations of better-than-dead (BTD) states only, as both studies used the same time trade-off (TTO) method for these states. For worse-than-dead (WTD) states, the 2017 study used the lead-time TTO and the 2002 study used the conventional TTO, which necessitated transformation. Regression models were fitted to BTD values to estimate time-specific differences, adjusting for respondent characteristics. Secondary analyses examined models that fitted WTD values (using linear and nonlinear transformations of the 2002 data) and all values. The adjusted BTD-only model showed mean values were higher for 2017 compared with 2002 (βY2017=0.05, P<0.001). WTD-only models showed negative changes over time but that were dependent on the transformation method (linear βY2017=-0.72; nonlinear βY2017=-0.35; both P<0.001). Using all values, 2017 mean valuations were lower using a linear transformation (βY2017=-0.11; P<0.001) but did not differ with the nonlinear transformation. Individuals in 2017 are generally less willing to trade quantity for quality of life compared with 2002. This study provides evidence of time-specific differences in a society's preferences, suggesting that the era in which values were elicited may be an important reason to consider updating societal value sets.

Exploring the Issues of Valuing Child and Adolescent Health States Using a Mixed Sample of Adolescents and Adults.

Preferences for child and adolescent health states used to generate health state utility values can be elicited from adults, young adults, adolescents, or combinations of these. This commentary paper provides a critical overview of issues and implications arising from valuing child and adolescent health states using a novel approach of a mixed sample of adolescents and adults. The commentary is informed by critical analysis of normative, ethical, practical and theoretical arguments in the health state valuation literature. Discussion focusses upon adolescent empowerment, understanding and psychosocial maturity; ethical concerns; elicitation tasks; perspective; and selection of sample proportions across adolescents and adults. It is argued that valuation of child and adolescent health states by both adolescents and adults could involve all participants completing the same preference elicitation task using the same perspective (e.g. time trade-off imagining they are living in the health state), and all preferences being modelled to generate a combined value set that reflects both adolescent and adult preferences. It is concluded that the valuation of child and adolescent health states by a mixed adolescent and adult sample appears feasible and has the advantage that it includes some of the population who can potentially experience the health states, thus enabling adolescents to express their views around matters that may affect them, and the population that are taxpayers and voters. However, both the relative proportion of adults and adolescents to include in a valuation sample and the elicitation technique require careful consideration.

Exploration of the Reasons Why Health State Valuation Differs for Children Compared With Adults: A Mixed Methods Approach

ObjectivesEvidence comparing utilities for adults and children consistently report higher utility values for child health states. This study investigates the reasons why child health states are valued differently. MethodsA total of 80 respondents (United Kingdom, Belgium, The Netherlands) participated in 1.5-hour face-to-face interviews. Respondents valued 4 health states from 2 perspectives (8-year-old child, 40-year-old adult) using visual analog scale and time trade-off. A total of 32 respondents participated in think-aloud interviews. Audio recordings were analyzed by 2 independent coders using NVIVO software. Statements, nodes, and themes were reviewed cyclically until consensus was reached. ResultsQualitative results: a total of 5 themes were identified in the data regarding child and adult valuation—intergenerational responsibility and dependency (childhood is crucial for forming life skills based on new experiences; adulthood is an important time to take care of the family), staying alive is important (life is worth living even with impaired health-related quality of life (HRQoL), for children and adults), awareness of poor HRQoL and ability to make decisions (children have difficulties comprehending poor HRQoL and their parents make their healthcare decision; adults can assess their own HRQoL and decide for themselves), coping ability (children are flexible and resilient; adults have experience with dealing with difficulties), and practical organization of care (children are cared for by their parents; adults are able to organize and pay for care). Mixed methods: comparing qualitative statements with respondents’ higher utilities for child health states confirmed concordance between results. ConclusionsQuality-adjusted life-years are interpreted differently for children and adults. Child-specific value sets are needed to reflect society’s preferences and to adequately conduct health technology assessment of pediatric treatments.

‘Like holding the axe on who should live or not’: adolescents’ and adults’ perceptions of valuing children’s health states using a standardised valuation protocol for the EQ-5D-Y-3L

PurposeThere is an increasing interest for using qualitative methods to investigate peoples’ cognitive process when asked to value health states. A standardised valuation protocol for the EQ-5D-Y-3L instrument was recently developed. Little is known regarding how people think, reason, and feel when asked to value health states for children. The aim was to explore how adolescents and adults perceive the task of valuing children’s health states using the standardised valuation protocol.MethodsThis was a qualitative study where adults (n = 10) and adolescents (n = 10) from the general population participated in individual video-interviews. Initially, participants reported their own health with the EQ-5D-3L instrument. Then they were asked to complete several valuations tasks for a 10-year-old child according to the standardised valuation protocol, followed by a semi-structured interview with open-ended questions to further explore participants’ perceptions. A qualitative content analysis was performed.ResultsThe two main categories that emerged from the data were ‘Thoughts and feelings when valuing children’s health states’ and ‘Strategies when valuing children’s health states’. Participants expressed feeling doubt, awfulness and being reluctant to trade-off life years, and questioned who has the right to value health states for children. Experience and point of view were strategies participants used to complete the valuation tasks.ConclusionThe findings from the present study can contribute to the understanding and interpretation of quantitative results where the standardised valuation protocol has been used to derive values for the EQ-5D-Y-3L. Furthermore, results of the study support the feasibility of including adolescents in valuation studies.

Determinants of Health Preferences Using Data from the Egyptian EQ-5D-5L Valuation Study.

ObjectiveThe aim of this study was to explore the impact of sociodemographic characteristics and illness experience on time trade-off (TTO)-based utility scores using data from the EQ-5D-5L Egyptian valuation study.MethodsData were from the Egyptian valuation study that was conducted using the adapted translated version of the EQ-VT to develop the Egyptian Tariff for the EQ-5D-5L based on preferences of the Egyptian population. Data were analysed using a series of univariate and multivariable censored linear regression models adjusted for severity of health states where the dependent variable was the TTO scores and the independent variables included age, sex, education, geographical region, dwelling, marital status, number of people in the household, employment status, having health insurance, number of chronic conditions, previous experience with illness, and self-rated health.ResultsAge, sex, education, marital status, dwelling, region of residence, health insurance and multimorbidity were significantly associated with health state valuations, while employment status, number of people in a household, religion, and previous experience with illness had non-significant associations.ConclusionAge, sex and marital status are the main determinants of health state valuation in the Egyptian population, a finding consistent with those from other countries. Knowing these factors will help tailor health services provided and improve patient-centered care.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40271-022-00572-0.

Why Do Adults Value EQ-5D-Y-3L Health States Differently for Themselves Than for Children and Adolescents: A Think-Aloud Study

ObjectivesFollowing protocol, adults value EQ-5D-Y-3L health states from the perspective of a 10-year-old child. It remains unclear why adults value health states differently for themselves than for a 10-year-old child and whether the latter perspective is representative of adults’ preferences for the 8 to 15 years age range of the EQ-5D-Y-3L. This study examines the reasons underlying (potential) differences in adults’ health-state preferences for themselves, a 10-year-old child, and 15-year-old adolescent. MethodsWe conducted semistructured interviews using a think-aloud protocol with 25 participants who performed valuation tasks in July 2020 to August 2020. Using the Framework Method, we developed 28 categories grouped under 5 themes that illustrated the differences emerging from the interviews. ResultsParticipants (A) deemed it more straining to perform valuation tasks for a 10-year-old child and 15-year-old adolescent than for themselves, (B) had a stable self-image, but varied in whom they imagined as 10-year-old child and 15-year-old adolescent, (C) focused on different dimensions and levels for a 15-year-old adolescent than for a 10-year-old child and themselves, (D) had various thoughts about nonhealth-related factors that influenced their preferences, and (E) gave up relatively few life-years for a 10-year-old child and 15-year-old adolescent, also to avoid others bearing a grudge against them. ConclusionsOur results indicate that differences in adults’ health-state preferences for themselves and a 10-year-old child largely result from differences in thoughts about nonhealth-related factors. They further indicate that health-state preferences for a 10-year-old child may not be representative of such preferences for the full EQ-5D-Y-3L age range.

Cost-effectiveness analysis of nivolumab plus standard chemotherapy versus chemotherapy alone for the first-line treatment of unresectable advanced or metastatic gastric cancer, gastroesophageal junction cancer, and esophageal adenocarcinoma

Background Nivolumab plus standard chemotherapy has significant clinical benefits for unresectable advanced or metastatic gastric cancer, gastroesophageal junction cancer, and esophageal adenocarcinoma (GC/GEJC/EAC). However, nivolumab is expensive, necessitating a cost-effectiveness evaluation. Aim This study aimed to evaluate the cost-effectiveness of nivolumab plus standard chemotherapy vs. chemotherapy alone for unresectable advanced or metastatic GC/GEJC/EAC from the Chinese healthcare system perspective. This study was based on randomized clinical trial data from the CheckMate-649 clinical trial (NCT02872116) published in Lancet (June 2021). Method A Markov model was used to assess the cost-effectiveness of nivolumab plus standard chemotherapy versus chemotherapy alone for unresectable advanced or metastatic GC/GEJC/EAC. Drug costs were collected from Tianjin Medical Purchasing Center in 2021, and utility values of health states were obtained from the literature. The reliability of model was assessed with one-way and probabilistic sensitivity analyses. Main outcome measure The main outcomes were costs, quality-adjusted life-years (QALYs) and the incremental cost-effectiveness ratio (ICER). Results Over a 10-year horizon, the outputs were 1.19 QALYs at a cost of $78,814.9 and 0.88 QALYs at a cost of $19,522.3 with nivolumab plus chemotherapy and chemotherapy alone, respectively. The ICER for nivolumab plus chemotherapy versus chemotherapy alone was $191,266/QALY, exceeding the willingness-to-pay (WTP) threshold ($33,436/QALY). One-way sensitivity analysis revealed nivolumab cost was the most influential parameter. Conclusion Adding nivolumab is not cost-effective for unresectable advanced or metastatic GC/GEJC/EAC in the current Chinese healthcare environment.

Examining the Association between Polish Migrant Status and Health Preferences Using a Novel Application of a Smaller Design EQ-5D-5L Valuation Study.

IntroductionMigrants have different utilisation of healthcare services and health-related behaviours than host populations. A potential factor that may contribute to the notable differences in healthcare use and health-related behaviours between migrants and host populations is how these groups value health. Those who place a high value on health have greater healthcare-seeking practices than those who do not.ObjectiveThe aim of this study was to examine how Polish migrants and native Irish differ in health state utility valuations using a novel application of a smaller design EQ-5D-5L valuation study.MethodsThis study uses health preferences as a predictor of how one values health. We examined the EQ-5D-5L health preferences of 119 Polish migrants and 123 native Irish, both residing full-time in Ireland. To do so, we used a novel application of a smaller design EQ-5D-5L valuation study that consisted of 30 health states and a targeted sampling strategy coupled with a Bayesian statistical nonparametric model. We collected data from June 2018 to September 2019.ResultsOur results highlight that Polish migrants and native Irish differ in their health preferences for and valuation of severe health states. Polish migrants place meaningfully higher utility valuations of 0.1 or more on the three most severe health states compared with the native Irish.ConclusionThis study can provide an understanding of a potential new factor underpinning some of the disparities in healthcare utilisation and health-related behaviours among migrants and host populations in Europe. This study also provides proof of principle for using a smaller design EQ-5D-5L valuation study to explore differences in health preferences among other minority subgroups, which can otherwise be hard to uncover when using the secondary analysis of national EQ-5D-5L valuation studies.Supplementary InformationThe online version contains supplementary material available at 10.1007/s41669-021-00314-2.

Exploring EQ-5D-Y-3L Experience-Based VAS Values Derived Among Adolescents.

ObjectivesThe EQ-5D-Y-3L is a generic health-related quality of life (HRQoL) instrument, developed from the adult version to be suitable for children and adolescents aged 8–15 years. To derive values for the EQ-5D-Y-3L different valuation methods and perspectives have been applied. The aim of this study was to explore EQ-5D-Y-3L experience-based visual analogue scale (VAS) values derived among adolescents.MethodsData were derived from a cross-sectional population survey administered via schools in 2014 to adolescents aged 13–18 years, in Sweden. Regression analyses were performed on individual data with the VAS value as dependent variable. Ordinary least-squares (OLS) and generalised linear models (GLM) were estimated with two dummy variables for each of the EQ-5D-Y-3L dimensions. Interaction variables were tested. One way of anchoring VAS at dead and full health by using the predicted values for worst and best health states defined by the EQ-5D-Y-3L descriptive system was explored.ResultsOf the 243 possible health states in EQ-5D-Y-3L, 92 were reported by the 6,468 respondents. The largest decrements in VAS values were observed for the dimension ‘feeling worried, sad or unhappy’ followed by ‘doing usual activities’. All models performed similarly in terms of monotonicity and goodness of fit but in terms of simplicity and understandability, the OLS main effect model was superior.ConclusionsWe have explored experience-based VAS values for the EQ-5D-Y-3L derived among adolescents. The findings suggest that it is possible for adolescents to value their own health state using the VAS, which makes it possible to capture aspects that are important for young people.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40258-021-00713-w.

The Online Elicitation of Personal Utility Functions (OPUF) tool: a new method for valuing health states.

Introduction Standard valuation methods, such as TTO and DCE are inefficient. They require data from hundreds if not thousands of participants to generate value sets. Here, we present the Online elicitation of Personal Utility Functions (OPUF) tool; a new type of online survey for valuing EQ-5D-5L health states using more efficient, compositional elicitation methods, which even allow estimating value sets on the individual level. The aims of this study are to report on the development of the tool, and to test the feasibility of using it to obtain individual-level value sets for the EQ-5D-5L. Methods We applied an iterative design approach toadapt the PUF method, previously developed by Devlin et al., for use as a standalone online tool. Five rounds of qualitative interviews, and one quantitative pre-pilot were conducted to get feedback on the different tasks. After each round, the tool was refined and re-evaluated. The final version was piloted in a sample of 50 participants from the UK. A demo of the EQ-5D-5L OPUF survey is available at: https://eq5d5l.me Results On average, it took participants about seven minutes to complete the OPUF Tool. Based on the responses, we were able to construct a personal EQ-5D-5L value set for each of the 50 participants. These value sets predicted a participants' choices in a discrete choice experiment with an accuracy of 80%. Overall, the results revealed that health state preferences vary considerably on the individual-level. Nevertheless, we were able to estimate a group-level value set for all 50 participants with reasonable precision. Discussion We successfully piloted the OPUF Tool and showed that it can be used to derive a group-level as well as personal value sets for the EQ-5D-5L. Although the development of the online tool is stillin an early stage, there are multiplepotentialavenues forfurtherresearch.

Understanding community perception and disability weights - A qualitative exploration of reasons associated with values in two states of India.

Health state valuation attempts to evaluate health states based on the perception of individuals. The values are used to derive disability weights (DWs) -an important metric for estimation of disability-adjusted life years and thereby calculation of the burden of diseases. Several studies have calculated DWs using different methods of valuation, however, very few have attempted to explore the underlying cause for assigning values to different health states. This study aims to document the perceptions, preferences, and social context in assigning DWs to given health states. A total of 42 community members and 21 service providers (from public and private sectors) across urban and rural Odisha and Telangana were interviewed between July to September 2018. A face-to-face in-depth interview and a rank ordering technique through card sort exercise was employed to explore reasons and perceptions of individuals in the context of health states using the thematic framework approach. Six themes emerged through analysis: awareness of the health state, nature of the disease, disease consequences, treatment-related issues, social implications, and case burden. Each theme captured an individual's reason for valuing one health state as different from the other, with differences and/or similarities between community members and service providers. Our study provides a comprehensive comparison between contrasting groups of individuals, thereby suggesting mere acceptance of 'experts' reasoning may not always suffice. Further research studies in the future need to be conducted for a better insight into the health perspective of a culturally diverse community. It can also help estimate the burden of disease for decision making and resource allocation in developing countries.

P60 A New Online Tool for Valuing Health States: Eliciting Personal Utility Functions for the EQ-5D-5L

Standard health valuation methods, such as TTO or DCE are inefficient. They require data from hundreds if not thousands of participants to generate utility values (=value sets) for health descriptive systems. Here, we present the Online elicitation of Personal Utility Functions (OPUF) tool; a new type of online survey for valuing EQ-5D-5L health states using more efficient, compositional preference elicitation methods, which allows estimating value sets on the individual level. The Objectives: of this study are to report on the development of the tool, and to test the feasibility of using it to obtain individual-level value sets for the EQ-5D-5L.

Exploring Structural Uncertainty and Impact of Health State Utility Values on Lifetime Outcomes in Diabetes Economic Simulation Models: Findings from the Ninth Mount Hood Diabetes Quality-of-Life Challenge.

BackgroundStructural uncertainty can affect model-based economic simulation estimates and study conclusions. Unfortunately, unlike parameter uncertainty, relatively little is known about its magnitude of impact on life-years (LYs) and quality-adjusted life-years (QALYs) in modeling of diabetes. We leveraged the Mount Hood Diabetes Challenge Network, a biennial conference attended by international diabetes modeling groups, to assess structural uncertainty in simulating QALYs in type 2 diabetes simulation models.MethodsEleven type 2 diabetes simulation modeling groups participated in the 9th Mount Hood Diabetes Challenge. Modeling groups simulated 5 diabetes-related intervention profiles using predefined baseline characteristics and a standard utility value set for diabetes-related complications. LYs and QALYs were reported. Simulations were repeated using lower and upper limits of the 95% confidence intervals of utility inputs. Changes in LYs and QALYs from tested interventions were compared across models. Additional analyses were conducted postchallenge to investigate drivers of cross-model differences.ResultsSubstantial cross-model variability in incremental LYs and QALYs was observed, particularly for HbA1c and body mass index (BMI) intervention profiles. For a 0.5%-point permanent HbA1c reduction, LY gains ranged from 0.050 to 0.750. For a 1-unit permanent BMI reduction, incremental QALYs varied from a small decrease in QALYs (−0.024) to an increase of 0.203. Changes in utility values of health states had a much smaller impact (to the hundredth of a decimal place) on incremental QALYs. Microsimulation models were found to generate a mean of 3.41 more LYs than cohort simulation models (P = 0.049).ConclusionsVariations in utility values contribute to a lesser extent than uncertainty captured as structural uncertainty. These findings reinforce the importance of assessing structural uncertainty thoroughly because the choice of model (or models) can influence study results, which can serve as evidence for resource allocation decisions.HighlightsThe findings indicate substantial cross-model variability in QALY predictions for a standardized set of simulation scenarios and is considerably larger than within model variability to alternative health state utility values (e.g., lower and upper limits of the 95% confidence intervals of utility inputs).There is a need to understand and assess structural uncertainty, as the choice of model to inform resource allocation decisions can matter more than the choice of health state utility values.

A Systematic Review of Economic Evaluations of Active Tuberculosis Treatments.

Background: The disease burden of active tuberculosis (TB) is considerable, but systematic reviews of economic evaluations of active TB treatments are scarce. Methods: PubMed, EMBASE, and the Cochrane Library databases were used to search for articles on cost-effectiveness analysis or cost-utility analysis that economically evaluated active TB treatments, which were then systematically reviewed by two independent reviewers. We extracted vital components of the included studies, such as country, population, intervention/comparator, primary outcome, values of outcomes, thresholds, model type, time horizon, and health states included in the model. Results: Seventeen studies were included in this systematic review. Thirteen dealt with interventions of medications, and the remaining four compared care strategies. The Markov model was the most commonly used tool to compare medications, whereas studies on care plans mainly used decision trees. The most commonly used primary outcome was disability-adjusted life years, followed by quality-adjusted life years. For treatment-naïve TB, the 4-month regimen was more cost-effective than the 6-month regimen mainly in low- and middle-income countries. For multidrug-resistant TB, a bedaquiline-based regimen was cost-effective. For multidrug-resistant TB, decentralized care that employed the use of home or mobile devices was more cost-effective than hospital-based centralized care in low- and middle-income countries. Conclusion: New treatment strategies to improve therapeutic outcomes by enhancing treatment adherence, such as regimens with shorter durations (2 or 4 months) and decentralized care, or new anti-TB agents (e.g., bedaquiline) have been suggested as cost-effective interventions for active TB. This review provides information on the economic evaluation of active TB from good-quality studies, thus aiding the future economic evaluation of active TB.

Challenges in Using Recommended QualityofLife Measures to Assess Fluctuating Health: A Think-Aloud Study to Understand How Recall and Timing of Assessment Influence Patient Responses.

BackgroundIt can be challenging to measure quality of life to calculate quality-adjusted life-years in recurrent fluctuating health states, as quality of life can constantly change. It is not clear how patients who experience fluctuations complete measures and how assessment timing and recall influence responses.ObjectiveWe aimed to understand how patients with fluctuating health complete widely recommended and commonly used measures (EQ-5D-5L, EORTC QLQ-C30 and SF-12) and the extent to which the recall period (‘health today’, ‘past week’ and ‘past 4 weeks’) and timing of assessment influence the way that patients complete these questionnaires.MethodsTwenty-four adult patients undergoing chemotherapy for urological, gynaecological or bowel cancers in the UK participated in think-aloud interviews, while completing the measures, completed a pictorial task illustrating how quality of life changed during the chemotherapy cycle and took part in semi-structured interviews. Transcripts were analysed using constant comparison.ResultsPatients were consistent in describing their quality of life as changing considerably throughout a chemotherapy cycle. The shorter recall period of ‘health today’ does not adequately represent patients’ quality of life because of fluctuations, patients remarked they could give a different answer depending on the timing of assessment, and many struggled to combine the “ups and downs” to answer measures with longer recall (‘past week’ and ‘past 4 weeks’). Across all measures, patients attempted to provide averages, adopt the peak-end rule or focus on the best part of their experience. Patients commonly used more than one approach when completing a given questionnaire as well as across questionnaires.ConclusionsPatients who experience recurrent fluctuations in health are unable to provide meaningful responses about their quality of life when completing quality-of-life measures due to the recall period and timing of assessment. The use of such responses to calculate health state values in economic evaluations to inform resource allocation decisions in fluctuating conditions must be questioned.Supplementary InformationThe online version contains supplementary material available at 10.1007/s40271-021-00555-7.

Not all respondents use a multiplicative utility function in choice experiments for health state valuations, which should be reflected in the elicitation format (or statistical analysis).

Discrete choice experiments (DCEs) that include health states and duration are becoming a common method for estimating quality‐adjusted life year (QALY) tariffs. These DCEs need to be analyzed under the assumption that respondents treat health and duration multiplicatively. However, in the most commonly used DCE duration format there is no guarantee that respondents actually do so; in fact, respondents can easily simplify the choice tasks by considering health and duration separately. This would result in valid DCE responses but preclude subsequent QALY tariff calculations. Using a Bayesian latent class model and data from two existing valuation studies, our analyses confirm that in both datasets the majority of respondents do not appear to have used a multiplicative utility function. Moreover, a statistical correction for respondents who used an incorrect function changes the range of the QALY weights. Hence our results imply that one can neither assume that respondents use the theoretically required multiplicative utility function nor assume that the type of utility function that respondents use does not affect the estimated QALY weights. As a solution, we advise researchers to use an alternative, more constrained DCE elicitation format that avoids these behavioral problems.

A Bayesian Nonparametric Approach for Modeling SF-6D Health State Utility Scores

ObjectivesTypically, models that were used for health state valuation data have been parametric. Recently, many researchers have explored the use of nonparametric Bayesian methods in this field. In this article, we report on the results from using a nonparametric model to predict a Bayesian short-form 6-dimension (SF-6D) health state valuation algorithm along with estimating the effect of the individual characteristics on health state valuations. MethodsA sample of 126 Lebanese members from the American University of Beirut valued 49 SF-6D health states using the standard gamble technique. Results from applying the nonparametric model were reported and compared with those obtained using a standard parametric model. The covariates’ effect on health state valuations was also reported. ResultsThe nonparametric Bayesian model was found to perform better than the parametric model at (1) predicting health state values within the full estimation data and in an out-of-sample validation in terms of mean predictions, root mean squared error, and the patterns of standardized residuals and (2) allowing for the covariates’ effect to vary by health state. The findings also suggest a potential age effect with some gender effect. ConclusionsThe nonparametric model is theoretically more flexible and produces better utility predictions from the SF-6D than previously used classical parametric model. In addition, the Bayesian model is more appropriate to account the covariates’ effect. Further research is encouraged.

Time trade-off with someone to live for: impact of having significant others on time trade-off valuations of hypothetical health states

BackgroundThe TTO task involves giving up life years, i.e. living a shorter life, to avoid an undesirable health state. Despite being a hypothetical task, some respondents take other life factors into account when completing the task. This study explored the effect of having children and/or a partner on TTO valuations of hypothetical EQ-5D-5L health states in a valuation study of the general population.MethodsThe study used TTO data collected in a Norwegian EQ-5D-5L valuation study in 2019–2020, by one-to-one pc-assisted interviews following the EQ-VT protocol. We used regression modelling to determine the effect of significant others (having children or a partner) on disutility per health state from the TTO valuations.Results430 respondents were included [mean age 43.8 (SD 15.9) years, 58% female, 48% with children, 68% with a partner, 25% with neither children nor partner]. Having children and/or a partner was associated with lowered willingness to trade life years translating to higher elicited health state utilities (p < 0.01).ConclusionHaving significant others, or the lack of having significant others, was associated with respondents’ valuation of hypothetical health states using TTO, more so than traditional sampling variables such as age and sex. Inadequate representativeness in terms of having significant others could bias health state preference values in valuation studies.