EuroQol Protocols for Time Trade-Off Valuation of Health Outcomes

Valuation Survey of EQ-5D-Y Based on the International Common Protocol: Development of a Value Set in Japan

BACKGROUND

EQ-5D-Y is a preference-based measure for children and adolescents (aged 8-15 y). This is the first study to develop an EQ-5D-Y value set for converting EQ-5D-Y responses to index values.

METHODS

We recruited 1047 respondents (aged 20-79 y) from the general population, stratified by gender and age group, in 5 Japanese cities. All data were collected through face-to-face surveys. Respondents were asked to value EQ-5D-Y states for a hypothetical 10-y-old child from a proxy perspective using composite time tradeoff (cTTO) and a discrete choice experiment (DCE). The discrete choice data were analyzed using a mixed logit model. Latent DCE values were then converted to a 0 (death)/1 (full health) scale by mapping them to the cTTO values.

RESULTS

The mean observed cTTO value of the worst health state [33333] was 0.20. Analysis of the DCE data showed that the coefficients of the domains related to mental functions ("Having pain or discomfort" and "Feeling worried, sad, or unhappy") were larger than those for the domains related to physical and social functions. By converting latent DCE values to a utility scale, we constructed a value set for EQ-5D-Y. No inconsistencies were observed. The minimum predicted score was 0.288 [33333], and the second-best score was 0.957 [12111].

CONCLUSION

A value set for EQ-5D-Y was successfully constructed. This is the first survey of an EQ-5D-Y value set. Interpreting the differences between EQ-5D-Y and EQ-5D-5L value sets is a future task with implications for health care policy.

Increasing respondent engagement in composite time trade-off tasks by imposing three minimum trade-offs to improve data quality

BACKGROUND

Web-based surveys are increasingly utilized for health valuation studies but may be more prone to lack of engagement and, therefore, poor data validity. The objective of this study was to evaluate the effect of imposed engagement (i.e., at least three trade-offs) in the composite time trade-off (cTTO) task.

METHODS

The EQ-5D-5L valuation study protocol and study design were adapted for online, unsupervised completion in two arms: base case and engagement. Validity of preferences was assessed using the prevalence of inconsistent valuations and expected patterns of TTO values. Respondent task engagement was measured using time per task. Value sets were generated using linear regression with a random intercept (RILR).

RESULTS

The base case (n = 501) and engagement arms (n = 504) clustered at different TTO values: [base case] 0, 1; [engagement] -0.5, 0.45, 0.6. Mean TTO values were lower for the engagement arm. Engagement respondents did not spend more time per TTO task: [base case] 63.3 s (SD 77.9 s); [engagement] 64.7 s (SD 73.3 s); p = 0.36. No significant difference was found between arms for prevalence of respondents with at least one inconsistent TTO value: [base case] 61.1%; [engagement] 63.5%; p = 0.43. Both value sets had significant intercepts far from 1: [base case] 0.846; [engagement] 0.783. The relative importance of the EQ-5D dimensions also differed between arms.

CONCLUSIONS

Both online arms had poor quality data. A minimum trade-off threshold did not improve engagement nor face validity of the data, indicating that modifications to the number of iterations are insufficient alone to improve data quality/validity of online TTO studies.

Assessing the Appropriateness of the EQ-5D for Duchenne Muscular Dystrophy: A Patient-Centered Study

Background

Duchenne muscular dystrophy is a rare degenerative neuromuscular disorder with pediatric onset. Recent approvals in Duchenne have placed attention on the economic evaluation in pricing and reimbursement decisions across a range of rare conditions. We sought to assess the appropriateness of the EQ-5D, a common measure of generic health state utility, for use among patients and caregivers affected by Duchenne.

Methods

An international, cross-sectional sample of adults with Duchenne and caregivers reported patient health status using self- or proxy-reported EQ-5D-3L. Appropriateness was assessed across 6 domains of concern raised by stakeholders in Duchenne. These concerns were that the EQ-5D/EQ-VAS would not capture meaningful differences in health status, correlate with disease-specific measures, reflect real health status, exhibit face validity, be accurately interpreted, and be low burden. We evaluated these concerns by comparing EQ-5D index score and EQ-VAS scores to other condition-specific functional measures and open- and closed-ended questions.

Results

In total, 263 participants (74% response) completed the survey, 24% of whom were adult patients. Most participants lived in the United States or United Kingdom (58%). Patient age ranged from 1 to 48 y. EQ-5D index was higher in ambulatory than nonambulatory patients (0.60 v. 0.30, P < 0.001) and was negatively correlated with upper limb impairment ( r = 0.61, P < 0.001). Three-quarters of respondents agreed that EQ-5D measured real health status (74%). Most respondents interpreted EQ-VAS anchors of best and worst imaginable health as full health (61%) and death/near death (58%). Respondents indicated the EQ-5D was easy to understand (86%) and answer (71%).

Conclusions

Contrary to anecdotal concerns, we found support for the appropriateness of EQ-5D to assess health status in Duchenne. While other measures may be more sensitive to specific outcomes in Duchenne, there may be some value in results using the EQ-5D measure.

Valuing health-related quality of life using a hybrid approach: Tunisian value set for the EQ-5D-3L

OBJECTIVE

To develop a value set for EQ-5D-3L based on the societal preferences of the Tunisian population.

METHODS

A representative sample of the Tunisian general population was obtained through multistage quota sampling involving age, gender and region. Participants (n = 327), aged above 20 years, were interviewed using the EuroQol Portable Valuation Technology in face-to-face computer-assisted interviews. Participants completed 10 composite time trade-off (cTTO) and 10 discrete choice experiments (DCE) tasks. Utility values for the EQ-5D-3L health states were estimated using regression modeling. The cTTO and DCE data were analyzed using linear and conditional logistic regression modeling, respectively. Multiple hybrid models were computed to analyze the combined data and were compared on goodness of fit measured by the Akaike information criterion (AIC).

RESULTS

A total of 300 participants with complete data that met quality criteria were included. All regression models showed both logical consistency and significance with respect to the parameter estimates. A hybrid model accounting for heteroscedasticity presented the lowest value for the AIC among the hybrid models. Hence, it was used to construct the Tunisian EQ-5D-3L valuation set with a range of predicted values from - 0.796 to 1.0.

CONCLUSION

This study provides utility values for EQ-5D-3L health states for the Tunisian population. This value set will be used in economic evaluations of health technologies and for Tunisian health policy decision-making.

Preferences and Health-Related Quality-of-Life Related to Disease and Treatment Features for Patients with Hemophilia A in a Canadian General Population Sample

BACKGROUND

Current treatments for hemophilia A in Canada include on-demand treatment as bleeds occur and regular intravenous prophylactic factor VIII (FVIII) infusions. The subcutaneous therapy emicizumab was recently approved for treatment of hemophilia A. The objective of this study was to estimate utility values associated with hemophilia A health and treatment states from a Canadian societal perspective, including preferences related to treatment efficacy and frequency and route of administration.

METHODS

A vignette-based time trade-off (TTO) utilities elicitation was undertaken in Canadian adults to compare preferences for six hemophilia health states describing prophylactic and on-demand treatment, with varying bleed rates and frequency of treatment administration. A convenience sample was recruited via market research panels and snowball sampling. Health state/vignette definitions were informed by clinical experience, clinical trial results regarding bleed frequency, and validated by qualitative interviews of hemophilia patients and caregivers (n=10). Utilities were estimated via an online, trained interviewer-guided, vignette-based TTO exercise, where respondents valuated health states describing hemophilia patients (adults or children) receiving subcutaneous prophylaxis, intravenous prophylaxis, and on-demand treatments. Analyses included a descriptive analysis by health state; a mixed-effects analysis of utility values adjusted for subcutaneous vs infusion-based therapies and number of bleeds; and for prophylactic regimens, an analysis of utilities by frequency of infusions or injections.

RESULTS

TTO interviews were conducted with 82 respondents. Mean utilities [95% CI] were highest for subcutaneous prophylaxis (0.90 [0.87-0.93]), followed by intravenous prophylaxis (0.81 [0.78-0.85]), and on-demand treatment (0.70 [0.65-0.76]). In regression analysis, subcutaneous treatment health states were associated with a utility increment of +0.1112. Additional bleeds and more frequent infusions were associated with lower utility values (-0.0027 per bleed and -0.0003 per infusion).

CONCLUSION

Subcutaneous prophylaxis is associated with higher utility values compared to intravenous prophylactic and on-demand treatment, while increased bleeds and infusions are associated with reduced utility.

SF-6Dv2 preference value set for health utility in food allergy

BACKGROUND

The lack of a value set allowing the calculation of QALY is an important limitation when establishing the value of emerging therapies to treat food allergy. The aim of this study was to develop a Short-Form Six-Dimension version 2 (SF-6Dv2) preference value set for the calculation of health utility from the Canadian food-allergic population.

METHODS

Two hundred ninety-five parents of patients aged 0-17 years old and 154 patients aged 12 years old and above with food allergy were recruited in clinic and online. Participants were asked to complete a self-administered online questionnaire including generic health-related quality of life questionnaires. Various health states described by the SF-6Dv2 were valued with time-trade-off and discrete choice experiments. Data from elicitation techniques were combined using the hybrid regression model.

RESULTS

A total of 241 parents and 125 patients performed 3904 time-trade-off and 5112 discrete choice experiments. Utility decrements were estimated for each level of each SF-6Dv2 dimension. Utility values calculated based on the validated preference set were in average 0.15 lower (95%CI: 0.12-0.18) and were poorly correlated (R²  = 0.46) with those derived from the EQ-5D-5L generic questionnaire in the same cohort.

CONCLUSION

A representative preference value set for patients with food allergy was determined using the SF-6Dv2 generic questionnaire. This adapted preference set will contribute to improve the validity of future utility estimates in this population for the appraisal of upcoming potentially impactful but sometimes costly therapies.

Multiplicative modelling of EQ-5D-3L TTO and VAS values

OBJECTIVE

This study aimed to test multiplicative modelling with EQ-5D-3L time-trade-off (TTO) and visual analogue scale (VAS) values.

METHODS

A multi-stage sampling design was adopted for the study and data collection took place in three phases in 2010, 2011, and 2012 in the Northern region of Malaysia. Face-to-face interviews involved respondents answering both 13 TTO and 15 VAS valuation tasks were carried out. Both additive and multiplicative model specifications were explored using the valuation data. Model performance was evaluated using out-of-sample predictive accuracy by applying the cross-validation technique. The distribution of the model values was also graphically compared on Bland-Altman plots and kernel density distribution curves.

RESULTS

Data from 630 and 611 respondents were included for analyses using TTO and VAS models, respectively. In terms of main-effects specifications, cross-validation results revealed a slight superiority of multiplicative models over its additive counterpart in modelling TTO values. However, both main-effects models had roughly equal predictive accuracy for VAS models. The non-linear multiplicative model with I32 term, MULT7_TTO, performed best for TTO models; while, the linear additive model with N3 term, ADD11_VAS, outperformed the other VAS models. Multiplicative modelling neither altered the dimensional rankings of importance nor did it change the distribution of values of the health states.

CONCLUSION

Using EQ-5D-3L valuation data, multiplicative modelling was shown to improve out-of-sample predictive accuracy of TTO models but not of VAS models.

Valuing health-related quality of life among the Indian population: a protocol for the Development of an EQ-5D Value set for India using an Extended design (DEVINE) Study

INTRODUCTION

Quality-adjusted life year (QALY) has been recommended by the government as preferred outcome measure for Health Technology Assessment (HTA) in India. As country-specific health-related quality of life tariff values are essential for accurate measurement of QALYs, the government of India has commissioned the present study. The aim of this paper is to describe the methods for the Development of an EQ-5D Value set for India using an Extended design (DEVINE) Study. Additionally, this study aspires to establish if the design of 10-time trade-off (TTO) blocks is enough to generate valid value sets.

METHODS AND ANALYSIS

A cross-sectional survey using the EuroQol Group's Valuation Technology (EQ-VT) will be undertaken in a sample of 2700 respondents selected from six different states of India using a multistage stratified random sampling technique. The participants will be interviewed using computer-assisted personal interviewing technique. The TTO valuation will be done using 10 composite TTO (c-TTO) tasks and 7 discrete choice experiment (DCE) tasks. Hybrid modelling approach using both c-TTO and DCE data to estimate the potential value set will be applied. Values of all 3125 health states will be predicted using both the conventional EQ-VT design of 10 blocks of 10 TTO tasks, and an extended design of 18 blocks of 10 TTO tasks. The potential added value of the eight additional blocks in overall validity will be tested. The study will deliver value set for India and assess the adequacy of existing 10-blocks design to be able to correctly predict the values of all 3125 health states.

ETHICS AND DISSEMINATION

The ethical approval has been obtained from Institutional Ethics Committee of PGIMER, Chandigarh, India. The anonymised EQ-5D-5L value set will be available for general use and in the HTAs commissioned by India's central HTA Agency.

Testing the "Nonstopping" Time Trade-Off: Is It Better Than the Composite Time Trade-Off?

OBJECTIVES

There are several issues of concern for the composite time trade-off (c-TTO) used to estimate EQ-5D-5L value sets. The "nonstopping" TTO (n-TTO) differs from the c-TTO mainly in 2 aspects: (1) n-TTO uses a standardized top-down or bottom-up routing; and (2) n-TTO continues when indifference is indicated by respondents. In this study, we aimed to test the feasibility of n-TTO and compared it with c-TTO.

METHODS

The study was conducted in parallel in Norway and Singapore. In both countries, members of the general population were invited to complete 10 n-TTO or c-TTO tasks. Acceptability and feasibility of n-TTO were assessed using respondents' feedback, administration time, and valuation success rate. Characteristics of the TTO data derived from c-TTO and n-TTO tasks were examined at task, individual, as well as group levels.

RESULTS

In both Norway and Singapore, the success rate of n-TTO tasks was high (> 95%) and the n-TTO tasks took less time to complete than the c-TTO tasks, and there were fewer or smaller "spikes" in the distributions of n-TTO data compared to c-TTO data. In Norway, the individual-level n-TTO and c-TTO data had similar distribution and logical consistency profiles. In Singapore, n-TTO was inferior to c-TTO in logical consistency; however, a similar degree of nonmonotonicity was observed in modeling of n-TTO and c-TTO data.

CONCLUSIONS

The noniterative n-TTO appeared to be feasible and may generate data with better distribution in shorter time than c-TTO. Further research is needed to assess this new health-state valuation method.

Health economic evaluation of gene replacement therapies: methodological issues and recommendations

Objective: To provide recommendations for addressing previously identified key challenges in health economic evaluations of Gene Replacement Therapies (GRTs), including: 1) the assessment of clinical effectiveness; 2) the valuation of health outcomes; 3) the time horizon and extrapolation of effects beyond trial duration; 4) the estimation of costs; 5) the selection of appropriate discount rates; 6) the incorporation of broader elements of value; and 7) affordability. Methods: A literature review on economic evaluations of GRT was performed. Interviews were conducted with 8 European and US health economic experts with experience in evaluations of GRT. Targeted literature reviews were conducted to investigate further potential solutions to specific challenges. Recommendations: Experts agreed on factors to be considered to ensure the acceptability of historical cohorts by HTA bodies. Existing prospective registries or, if not available, retrospective registries, may be used to analyse different disease trajectories and inform extrapolations. The importance of expert opinion due to limited data was acknowledged. Expert opinion should be obtained using structured elicitation techniques. Broader elements of value, beyond health gains directly related to treatment, can be considered through the application of a factor to inflate the quality-adjusted life years (QALYs) or a higher cost-effectiveness threshold. Additionally, the use of cost-benefit analysis and saved young life equivalents (SAVE) were proposed as alternatives to QALYs for the valuations of outcomes of GRT as they can incorporate broader elements of value and avoid problems of eliciting utilities for paediatric diseases. Conclusions: While some of the limitations of economic evaluations of GRT are inherent to limited clinical data and lack of experience with these treatments, others may be addressed by methodological research to be conducted by health economists.

Incorporating Mortality in Health Utility Measures

The creation of multiattribute health utility systems requires design choices that have profound effects on the utility model, many of which have been documented and studied in the literature. Here we describe one design choice that has, to the best of our knowledge, been unrecognized and therefore ignored. It can emerge in any multiattribute decision analysis in which one or more essential outcomes cannot be described in terms of the multiattribute space. In health applications, the state of being dead is such an outcome. When the remaining health is conceptualized as a multidimensional space, determining the utility of the state of being dead requires using the interval-scale properties of cardinal utility, combined with elicited utilities for the state of being dead and the all-worst state, to produce a utility function in which the state of being dead has a utility of 0 and full health has a utility of 1 (i.e., the quality-adjusted life-year scale). Although previously unrecognized, there are two approaches to accomplish that step, and they produce different results in almost all cases. As a corollary, the choice of approach determines the proportion of states rated as worse than dead by the system. For example, in the Health Utility Index 3 (HUI3), the method used classifies 78% of the 972,000 unique health states in the classification system as worse than dead, and that proportion increases to 85% when the HUI3 is recalculated using the alternative approach. Studies of populations with significant morbidity are the most likely to be sensitive to the design choice. Those who design utility measures should be aware that they are using a researcher degree of freedom when they decide how to scale the state of being dead.

Do Discrete Choice Experiments Approaches Perform Better Than Time Trade-Off in Eliciting Health State Utilities? Evidence From SF-6Dv2 in China

OBJECTIVES

To explore the acceptability, consistency, and accuracy of eliciting health state utility values using discrete choice experiment (DCE) and DCE with life duration dimension (DCE_TTO) as compared with conventional time trade-off (TTO) by using the SF-6Dv2.

METHODS

During face-to-face interviews, a representative sample of the general population in Tianjin, China, completed 8 TTO tasks and 10 DCE/DCE_TTO tasks, with the order of TTO and DCE/DCE_TTO being randomized. The fixed-effect model and conditional logit models were used for TTO and DCEs data estimation, respectively. Acceptability was assessed by self-reported difficulties in understanding/answering. Consistency was observed by the monotonicity of model coefficients. Accuracy was evaluated by investigating differences between observed and predicted TTO values using intraclass correlation coefficient, mean absolute difference, and root mean square difference.

RESULTS

A total of 503 respondents (53.7% male; range, 18-86 years) were included, with comparable characteristics between respondents who completed DCE (N = 252) and DCE_TTO (N = 251). No significant difference was observed in self-reported difficulties among 3 approaches. The monotonicity of coefficients could not be achieved for 2 DCE approaches, even when combining the inconsistent levels. The health state utility values generated by DCE were generally higher than those generated by TTO, whereas DCE_TTO was lower than TTO. The TTO had a better prediction accuracy than the DCEs.

CONCLUSIONS

Two DCE approaches are feasible for eliciting health state utility values; however, they are not considered to be easier to understand/answer than TTO. There are systematic differences in the health state utility values generated by 3 approaches. The issue of non-monotonicity from 2 DCE approaches remains a concern.

An exploration of methods for obtaining 0 = dead anchors for latent scale EQ-5D-Y values

OBJECTIVES

Discrete choice experiments (DCEs) can be used to obtain latent scale values for the EQ-5D-Y, but these require anchoring at 0 = dead to meet the conventions of quality-adjusted life year (QALY) estimation. The primary aim of this study is to compare four preference elicitation methods for obtaining anchors for latent scale EQ-5D-Y values.

METHODS

Four methods were tested: visual analogue scale (VAS), DCE (with a duration attribute), lag-time time trade-off (TTO) and the location-of-dead (LOD) approach. In computer-assisted personal interviews, UK general public respondents valued EQ-5D-3L health states from an adult perspective and EQ-5D-Y health states from a 10-year-old child perspective. Respondents completed valuation tasks using all four methods, under both perspectives.

RESULTS

349 interviews were conducted. Overall, respondents gave lower values under the adult perspective compared to the child perspective, with some variation across methods. The mean TTO value for the worst health state (33333) was about equal to dead in the child perspective and worse than dead in the adult perspective. The mean VAS rescaled value for 33333 was also higher in the child perspective. The DCE produced positive child perspective values and negative adult perspective values, though the models were not consistent. The LOD median rescaled value for 33333 was negative under both perspectives and higher in the child perspective.

DISCUSSION

There was broad agreement across methods. Potential criteria for selecting a preferred anchoring method are presented. We conclude by discussing the decision-making circumstances under which utilities and QALY estimates for children and adults need to be commensurate to achieve allocative efficiency.

QALY-time: experts' view on the use of the quality-adjusted LIFE year in COST-effectiveness analysis in palliative care

Background

The Quality-Adjusted Life Year (QALY) is internationally recognized as standard metric of health outcomes in cost-effectiveness analyses (CEAs) in healthcare. The ongoing debate concerning the appropriateness of its use for decision-making in palliative care has been recently mapped in a review. The aim was to report on and draw conclusions from two expert meetings that reflected on earlier mapped issues in order to reach consensus, and to advise on the QALY’s future use in palliative care.

Methods

A nominal group approach was used. In order to facilitate group decision making, three statements regarding the use of the QALY in palliative care were discussed in a structured way. Two groups of international policymakers, healthcare professionals and researchers participated. Data were analysed qualitatively using inductive coding.

Results

1) Most experts agreed that the recommended measurement tool for the QALYs ‘Q’ component, the EuroQol-5D (EQ-5D), is inappropriate for palliative care. A more sensitive tool, which might be based on the capabilities approach, could be used or developed. 2) Valuation of time should be incorporated in the ‘Q’ part, leaving the linear clock time in the ‘LY’ component. 3) Most experts agreed that the QALY, in its current shape, is not suitable for palliative care.

Conclusions

1) Although the EQ-5D does not suffice, a generic tool is needed for the QALY. As long as no suitable alternative is available, other tools can be used besides or serve as basis for the EQ-5D because of issues in conceptual overlap. 2) Future research should further investigate the valuation of time issue, and how best to integrate it in the ‘Q’ component. 3) A generic outcome measure of effectiveness is essential to justly allocate healthcare resources. However, experts emphasized, the QALY is and should be one of multiple criteria for choices in the healthcare insurance package.

Peruvian Valuation of the EQ-5D-5L: A Direct Comparison of Time Trade-Off and Discrete Choice Experiments

OBJECTIVES

(1) To produce Peruvian general population EQ-5D-5L value sets on a quality-adjusted life-year scale, (2) to investigate the feasibility of a "Lite" protocol less reliant on the composite time trade-off (cTTO), and (3) to compare cTTO and discrete choice experiment (DCE) value sets.

METHODS

A random sample of adults (N = 1000) in Lima, Arequipa, and Iquitos did a home interview; 300 were randomly selected to complete 11 cTTOs first. All respondents completed a DCE, including 10 latent-scale pairs (A/B) with 5 EQ-5D-5L attributes, and 12 matched pairs (A/B and B/C) with 5 EQ-5D-5L and one lifespan attributes. We estimated a cTTO heteroscedastic tobit (N = 300) model and 3 DCE Zermelo-Bradley-Terry models (N = 300, 700, and 1000).

RESULTS

Each model produced a consistent value set (20 positive incremental parameters). Nevertheless, their lowest quality-adjusted life-year values differed greatly (cTTO: -1.076 [N = 300]; DCE: -0.984 [300], 0.048 [700], -0.213 [1000]). Compared with the cTTO, the DCE (N = 300) produced different parameters (Pearson's correlation = 0.541), fewer insignificant parameters (0 vs 8), and fewer values less than 0 (26% vs 44%). Compared with the DCE (N = 300), the DCE (N = 700) produced higher values but similar parameters (Pearson's correlation = 0.800).

CONCLUSIONS

Besides producing EQ-5D-5L value sets for Peru, the results casts doubt about the feasibility of a Lite protocol like the one in this study. Additionally, fundamental differences between cTTO and DCE-without the existence of a gold standard-need further clarification. The choice between the two rational value sets produced in the current study is a matter of judgment and may have substantial policy implications.

An overview of the time trade-off method: concept, foundation, and the evaluation of distorting factors in putting a value on health

INTRODUCTION

Preference-based instruments measuring health status express the value of specific health states in a single number. One method used is time trade-off (TTO). Health-status values are key elements in calculating quality-adjusted life years (QALYs) and are pertinent for resource allocation. Since they are used in economic evaluations of healthcare, searching for a theoretical foundation of TTO in economics is justified.

AREA COVERED

This paper provides an overview of TTO, including its relation to economic theory, and discusses biases and distortions, compiled from recent and older research. Inconsistencies between TTO and random utility theory were detected; The TTO is confounded by time preferences and by respondents' life expectancies. TTO is cognitively challenging, therefore guidance during the interviews is needed, producing interview effects. TTO does not measure one thing at a time, nor are the values independent of other states that are being valued in the same task. That is, TTO does not exhibit theoretical measurement properties such as unidimensionality and the invariance principle.

EXPERT OPINION

We conclude that the TTO may be a pragmatic method of eliciting health state values, but the limitations in regard to measurement theory and practical elicitation problems makes it prone to inconsistencies and arbitrariness.

Elicitation of Norwegian EQ-5D-5L values for hypothetical and experience-based health states based on the EuroQol Valuation Technology (EQ-VT) protocol

INTRODUCTION

Norway is one of several European countries that lacks a national value set and scoring algorithm for the EuroQol five dimensions (EQ-5D). Recent studies have found differences between countries in terms of health values or preferences for health states described by instruments such as the EQ-5D. The project aims to model a national value set for the five level version of the EQ-5D based on values elicited from a representative sample of the Norwegian adult general population in terms of region, age, sex and level of education. Using a sampling strategy supporting the collection of values for both hypothetical and experienced health states, the study will have the additional aim of assessing the feasibility of collecting experience-based values in accordance with the latest EQ-5D valuation study protocol, and comparing values with those given for hypothetical health states.

METHODS AND ANALYSIS

Multistage random sampling and quota-sampling will contribute to representativeness. To increase the number of valuations of experienced health states, those with less than perfect health will be oversampled, increasing the total number of interviews from 1000 to 1300-1500. The most recent EQ-5D valuation protocol will be followed which includes computer assisted face-to-face, one-to-one interviews and use of composite time trade-off and discrete choice experiments.

ETHICS AND DISSEMINATION

The study has been reviewed and found to be outside of the scope of the ethics committee and thus not in need of ethical approval. The study findings will be disseminated through peer-reviewed publications, conference presentations and summaries for key stakeholders and partners in the field. The scoring algorithms will be available for widely used statistical software.

A vision 'bolt-on' increases the responsiveness of EQ-5D: preliminary evidence from a study of cataract surgery

OBJECTIVES

(1) To evaluate the effect of adding a vision dimension ('bolt-on') to the 5-level EQ-5D (EQ-5D-5L) and 3-level EQ-5D (EQ-5D-3L) on their responsiveness, and (2) to compare the responsiveness of a vision 'bolt-on' EQ-5D-3L (EQ-5D-3L + V) with SF-6D and Health Utilities Index Mark 3 (HUI3) to the benefit of cataract surgery.

METHODS

Sixty-three patients were assessed before and after their cataract surgery using the EQ-5D-3L, EQ-5D-5L, SF-6D, HUI3, as well as a 3-level and a 5-level vision dimension. Preference-based indices were calculated using available value sets for EQ-5D-3L, EQ-5D-3L + V, EQ-5D-5L, SF-6D, and HUI3, and non-preference-based indices were calculated using the sum-score method for EQ-5D-5L and EQ-5D-5L + V (vision bolt-on EQ-5D-5L). Responsiveness was assessed using the standardized response mean (SRM) and F-statistic.

RESULTS

Among preference-based indices, mean changes from pre to post-surgery in EQ-5D-3L + V and EQ-5D-3L indices were 0.031 and 0.018, respectively. The mean changes for EQ-5D-5L, SF-6D and HUI3 indices were 0.020, 0.012 and 0.105, respectively. The SRM (F-statistic) for EQ-5D-3L + V and EQ-5D-3L indices were 0.458 (13.2) and 0.098 (0.6), respectively. The responsiveness of EQ-5D-3L + V was better than EQ-5D-5L, SF-6D; the responsiveness of HUI3 was better than all other measures. Using non-preference-based indices, mean change for EQ-5D-5L + V and EQ-5D-5L were 0.067 and 0.017, respectively. The corresponding SRM (F-statistic) were 0.709 (31.7) and 0.295 (5.4).

CONCLUSIONS

Preliminary evidence from our study suggests that a vision 'bolt-on' may increase the responsiveness of EQ-5D-3L and EQ-5D-5L to change in health outcomes experienced by patients undergoing cataract surgery. In absence of the preference-based vision bolt-on EQ-5D-5L index, HUI3 was the most responsive measure.

Do people with private health insurance attach a higher value to health than those without insurance? Results from an EQ-5D-5 L valuation study in Ireland

BACKGROUND

Differences in healthcare use could relate to differences in the values assigned health as well as to differences in access. We sought to establish whether there existed evidence of differences in values assigned health states between individuals with and without insurance in Ireland.

METHODS

Using the EuroQol Valuation Technology (EQ-VT), EQ-5D-5 L valuation tasks were administered to a sample of 1160 residents of Ireland in 2015/16. Censored panel regression analyses were used to estimate the values assigned health states. Private insurance was entered among a range of covariates to explain health preferences as a binary variable. A range of confirmatory analyses were undertaken.

RESULTS

In the primary analysis, possession of private health insurance was not a significant determinant of health preferences. Across a range of confirmatory analyses limited evidence of any difference in values related to health insurance emerged.

CONCLUSIONS

Insurance status has been shown to be a significant determinant of healthcare utilization in Ireland after need has been controlled for. Our analysis provides no compelling evidence that meaningful differences exist in the values accorded health between those with and without health insurance.

Similar responses to EQ-5D-3L by two elicitation methods: visual analogue scale and time trade-off

Background

Health-related quality of life (HRQoL) is often measured using EQ-5D-3L by the elicitation methods of visual analogue scale (VAS) and time trade-off (TTO). Although many countries have constructed both national VAS and TTO value sets, the fact that VAS and TTO value sets produces different values bewilders researchers and policymakers. The aim of this study is to explore certain conditions which could yield similar value sets using VAS and TTO.

Methods

A homogeneous sample of medical school students was selected to value 18 hypothetical health states using VAS and TTO methods. The 18 hypothetical health states were produced by orthogonal design (L18, 2*3^7). The range of rescaled values was transformed into − 1 ~ 0 ~ 1. The investigations via different methods were carried out by computer-assisted personal interviewing with a wash-time interval of 72 h. Value sets for VAS and TTO were constructed using general least square regression models. Independent variables were composed of 10 dummy variables from 5 dimensions and including or omitting both constant and N3 terms.

Results

Three hundred thirteen medical students participated. The mean age was 21.03 ± 0.44 years and 56.2% were female. The four regression models (for each method with and without constant and N3 terms) were all statistically significant (P < 0.05) with high goodness-of-fit (Adj. R² > 0.94 and MAE < 0.033). Differences between the coefficients of the 10 dummy variables corresponding to each model were all less than 0.059. Pearson correlation coefficients between observed means and predicted values exceeded 0.981. Fitted curves of VAS and TTO largely coincided.

Conclusions

VAS and TTO can generate similar responses under certain conditions, suggesting that the two valuation methods could be equivalent intrinsically. The VAS method appears a more valid approach for valuation in the general population due to its greater simplicity and feasibility.

Comparing the EQ-5D-5L crosswalks and value sets for England, the Netherlands and Spain: Exploring their impact on cost-utility results

This study compares the five-level EuroQol five-dimension questionnaire (EQ-5D-5L) crosswalks and the 5L value sets for England, the Netherlands, and Spain and explores the implication of using one or the other for the results of cost-utility analyses. Data from two randomized controlled trials in depression and diabetes were used. Utility value distributions were compared, and mean differences in utility values between the EQ-5D-5L crosswalk and the 5L value set were described by country. Quality-adjusted life years (QALYs) were calculated using the area-under-the-curve method. Incremental cost-effectiveness ratios (ICERs) were calculated, and uncertainty around ICERs was estimated using bootstrapping and graphically shown in cost-effectiveness acceptability curves. For all countries investigated, utility value distributions differed between the EQ-5D-5L crosswalk and 5L value set. In both case studies, mean utility values were lower for the EQ-5D-5L crosswalk compared with the 5L value set in England and Spain, but higher in the Netherlands. However, these differences in utility values did not translate into relevant differences across utility estimation methods in incremental QALYs and the interventions' probability of cost-effectiveness. Thus, our results suggest that EQ-5D-5L crosswalks and 5L value sets can be used interchangeably in patients affected by mild or moderate conditions. Further research is needed to establish whether these findings are generalizable to economic evaluations among severely ill patients.

An EQ-5D-5L Value Set for Vietnam

PURPOSE

The objective of this study was to develop an EQ-5D-5L value set based on the health preferences of the general adult population of Vietnam.

METHODS

The EQ-VT protocol version 2.1 was applied. Multi-stage stratified cluster sampling was employed to recruit a nationally representative sample. Both composite time trade-off (C-TTO) and discrete choice experiment (DCE) methods were used. Several modelling approaches were considered including hybrid; tobit; panel and heteroscedastic models. First, models using C-TTO or DCE data were tested separately. Then possibility of combining the C-TTO and DCE data was examined. Hybrid models were tested if it was sensible to combine both types of data. The best-performing model was selected based on both the consistency of the results produced and the degree to which models used all the available data.

RESULTS

Data from 1200 respondents representing the general Vietnamese adult population were included in the analyses. Only the DCE Logit model and the regular Hybrid model that uses all available data produced consistent results. As the priority was to use all available data if possible, the hybrid model was selected to generate the Vietnamese value set. Mobility had the largest effect on health state values, followed by pain/discomfort, usual activities, anxiety/depression and self-care. The Vietnam values ranged from - 0.5115 to 1.

CONCLUSION

This is the first value set for EQ-5D-5L based on social preferences obtained from a nationally representative sample in Vietnam. The value set will likely play a key role in economic evaluations and health technology assessments in Vietnam.

EQ-5D-5L is More Responsive than EQ-5D-3L to Treatment Benefit of Cataract Surgery

BACKGROUND

It is not clear whether 5-level EQ-5D (EQ-5D-5L) utilities based on recently developed value sets are more responsive than 3-level EQ-5D (EQ-5D-3L) utilities.

OBJECTIVES

The study aims were to compare (1) the responsiveness of EQ-5D-5L and EQ-5D-3L utilities and (2) the responsiveness of these utilities with the Short Form-6 Dimension (SF-6D) and Health Utilities Index Mark 3 (HUI3) utilities to the treatment benefit of cataract surgery.

METHODS

A total of 148 patients were interviewed before and after their cataract surgery using EQ-5D-3L, EQ-5D-5L, SF-6D, and HUI3. Responsiveness was assessed for all measures using the mean change (post-treatment-pre-treatment), standardized effect size (SES), standardized response mean (SRM), and F-statistic.

RESULTS

Using the Singapore value sets, mean change for EQ-5D-3L and EQ-5D-5L utilities was 0.016 and 0.028, SES was 0.097 and 0.199; SRM was 0.091 and 0.196; and F-statistic was 1.2 and 5.7, respectively. Similar trends were observed using the UK/England EQ-5D value sets, although the magnitude was slightly smaller. The mean change, SES, SRM and F-statistics for SF-6D (UK value set) were 0.020, 0.234, 0.249, and 9.2, respectively. The values of mean change, SES, SRM and F-statistics for HUI3 (Canada value set) were 0.080, 0.472, 0.474, and 33.3, respectively.

CONCLUSIONS

The EQ-5D-5L utilities tend to be more responsive than the EQ-5D-3L utilities to treatment benefits of cataract surgery. The HUI3 utilities are more responsive than both the EQ-5D-5L and SF-6D, and SF-6D utilities may be slightly more responsive than the EQ-5D-5L for assessing patients undergoing cataract surgery.

Valuation of EQ-5D-3l Health States in Slovenia: VAS Based and TTO Based Value Sets

INTRODUCTION

The two primary objectives of this paper were (a) to develop first logically consistent TTO based EQ-5D-3L value sets for Slovenia and (b) to revisit earlier developed VAS based EQ-5D-3L value sets.

METHODS

Between September 2005 and April 2006, face-to-face interviews with 225 individuals in Slovenia were conducted. Protocols from the Measurement and Value of Health study were followed closely. Each respondent valued 15 health states out of a total of 23. Model selection was informed by the criteria monotonicity/logical consistency. Predictive accuracy was assessed in terms of mean square difference between out-of-sample predictions and corresponding observed means, as well as Lin's Concordance Correlation Coefficient.

RESULTS

Modelling was based on 2,717 VAS and 2,831 TTO values elicited from 225 respondents. A 6-parameter constrained regression model with a supplementary power term was selected for VAS and TTO value sets, as it produces monotonic values, and proved superior in terms of out-of-sample predictive accuracy over the tested alternatives.

CONCLUSION

This is the first EQ-5D-3L TTO based value set in Slovenia and the second in Central and Eastern Europe (besides Poland). It is also the first monotonic and logically consistent VAS value set in Central and Eastern Europe. Comparisons with Polish and UK TTO values show considerable differences, mostly due to mobility with having a substantially greater weight in Slovenia. The UK value set generally produces lower values and the Polish value set higher values for mild states.

Hybrid Methodology to Improve Health Status Utility Values Derivation Using EQ-5D-5L and Advanced Multi-Criteria Techniques

This paper presented a new approach to the calculation of quality-adjusted life years (QALY) based on multi-criteria decision-making (MCDM) methods and using the EQ-5D-5L questionnaire. The health status utility values were calculated through a hybrid methodology. We combined the analytic hierarchy process (AHP), the AHP with a D-number extended fuzzy preference relation (D-AHP), the fuzzy analytic hierarchy process (F-AHP), and the technique for order preference by similarity to the ideal solution (TOPSIS) to obtain individual and aggregated utility values. The preference data were elicited using a sample of individuals from a Colombian university. In all tested methods, the ordinal preferences were consistent, and the weights were compared using the Euclidean distance criterion (EDC). We identified F-AHP-TOPSIS as the optimal method; its benefits were associated with modeling the response options of the EQ-5D in linguistic terms, it gave the best approximation to the initial preferences according to EDC, and it could be used as an alternative to the known prioritization method. This hybrid methodology was particularly useful in certain medical decisions concerned with understanding how a specific person values his or her current health or possible health outcomes from different interventions in small population samples and studies carried out in low- and middle-low-income countries.

Elicitation of Health-Related Utility in Perianal Fistula in Crohn's Disease

BACKGROUND AND OBJECTIVE

Perianal fistulae are a common complication of Crohn's disease (CD) and pose a substantial burden on quality of life. Data capturing health-related utility associated with perianal fistulae in CD are scarce. The current study aims to value health states related to different stages of the disease to quantitatively evaluate the impact of complex perianal fistulae on CD patients' quality of life.

METHODS

Eight health state descriptions associated with complex perianal fistulae in CD were developed following qualitative research with patients and validation by clinicians. Following pre-testing, a survey was administered online in two samples of UK respondents: the general population and patients with CD. A choice-based valuation technique, the time trade-off (TTO), was used for direct utility measurement. CD patients also valued their current health state using the TTO. Exclusion criteria for respondents displaying logical inconsistencies were applied.

RESULTS

Usable responses were received from 835 respondents, reflective of the UK population in age and sex, in the general population survey and 162 CD patients in the patient survey. Non-remission states were valued much lower than the remission state by both samples, ranging from 0.20 for proctectomy with a negative outcome to 0.66 for chronic symptomatic fistulae with mild symptoms. Patients currently experiencing fistulae reported lower values for current health than those without fistulae.

CONCLUSION

Low utility values were assigned to the non-remission health states for perianal fistulae in CD by the general public and patients with CD. This demonstrates the high humanistic burden of inadequately managed perianal fistula in CD.

Examining the transnational health preferences of a group of Eastern European migrants relative to a European host population using the EQ-5D-5L

The concept of transnationalism may provide an alternative rationale to observed differences in patterns of migrant healthcare use and health-related behaviours. In this study, we examined the health preferences of Eastern European migrants residing in another European state relative to comparable natives through the prism of transnationalism. For the analysis, we focused on the health preferences of 87 Polish migrants living full-time in Ireland compared to 87 Irish natives. We used EQ-5D-5L composite Time Trade-Off (cTTO) utility data collected as part of the Irish value set during 2015/2016 to examine the health preferences of both groups. Propensity score matching was utilised to match comparable Irish respondents to Polish migrants with 1:1 matching. Since cTTO utility data is censored, a random effects Tobit model was used to explore differences in utility valuations, and in a secondary analysis, we examined the likelihood of applying a negative utility valuation using a random effects logit model. The results from this study demonstrate that on average Polish migrants apply a significantly greater disutility valuation to health states and are more likely to apply a negative utility valuation to a given health state when compared to comparable natives. Differences in utility valuations can be seen as indicative of time preference with a greater disutility valuation being associated with a higher rate of time preference. This finding may be suggestive of health-related behaviours, such as a greater likelihood of not engaging with preventive service use in as far as those with high rates of time preference have low uptake. Transnationalism can underpin the observed differences in health preferences between the Polish migrants and comparable Irish natives. Transnational ties shape health-related behaviours of migrants from the use of healthcare services to health preferences. The results of this study will be of interest to policymakers in Ireland and Europe.

Bayesian Hierarchical Models for Meta-Analysis of Quality-of-Life Outcomes: An Application in Multimorbidity

BACKGROUND

Health-related quality of life (HRQoL) is a key outcome in cost-utility analyses, which are commonly used to inform healthcare decisions. Different instruments exist to evaluate HRQoL, however while some jurisdictions have a preferred system, no gold standard exists. Standard meta-analysis struggles with the variety of outcome measures, which may result in the exclusion of potentially relevant evidence.

OBJECTIVE

Using a case study in multimorbidity, the objective of this analysis is to illustrate how a Bayesian hierarchical model can be used to combine data across different instruments. The outcome of interest is the slope relating HRQoL to the number of coexisting conditions.

METHODS

We propose a three-level Bayesian hierarchical model to systematically include a large number of studies evaluating HRQoL using multiple instruments. Random effects assumptions yield instrument-level estimates benefitting from borrowing strength across the evidence base. This is particularly useful where little evidence is available for the outcome of choice for further evaluation.

RESULTS

Our analysis estimated a reduction in quality of life of 3.8-4.1% per additional condition depending on HRQoL instrument. Uncertainty was reduced by approximately 80% for the instrument with the least evidence.

CONCLUSION

Bayesian hierarchical models may provide a useful modelling approach to systematically synthesize data from HRQoL studies.

Time Trade-off Utility Values in Noninfectious Uveitis

PURPOSE

To investigate time trade-off (TTO) utility values in patients with noninfectious uveitis and determine whether patient demographics and clinical characteristics are associated with utility scores.

DESIGN

Time trade-off utility analysis.

METHODS

Setting: A tertiary care uveitis center in San Francisco, California, USA.

PATIENT POPULATION

One hundred and four consecutive adults with noninfectious uveitis, enrolled between November 2016 and February 2017.

MAIN OUTCOME MEASURES

TTO utility values, as collected by an interviewer-guided survey. Information regarding general health, ocular symptoms, and religion was also collected and medical record review was conducted to record anatomic location of uveitis, disease activity, visual acuity, and treatments. Multivariable regression analysis with backward selection was used to identify variables associated with TTO values.

RESULTS

Median TTO score was 0.975 (interquartile range [IQR]: 0.8-1.0), corresponding to trading a median 1.28 years of remaining life for healthy eyes (IQR: 0-6.29). Regression analysis revealed that worse eye visual acuity, >6 months of oral corticosteroid use, and current antidepressant use were associated with lower TTO scores (P = .008, P = .006, P = .008, respectively), controlling for age and sex. In particular, patients who had been taking oral corticosteroids for more than 6 months, regardless of dose, were 10.5 times more likely to trade 20% or more years of remaining life (TTO ≤0.8) than patients not taking oral corticosteroids (95% confidence interval: 2.3, 48.1; P = .002).

CONCLUSIONS

Patients with noninfectious uveitis had measurable, though modest, reductions in quality of life, as assessed by TTO, and these decreases were significantly associated with visual acuity in the worse eye and long-term oral corticosteroid use.

Toward a Smaller Design for EQ-5D-5L Valuation Studies

BACKGROUND

To construct an EQ-5D-5L value set, the EuroQol Group developed a standard protocol named EuroQol Valuation Technology (EQ-VT), prescribing the valuation of 86 health states utilizing the composite time trade-off (cTTO) approach, and subsequently modeled the observed values to yield values for all 3125 states.

OBJECTIVE

A recent study demonstrated that a 25-state orthogonal design could provide as accurate predictions as the EQ-VT design applying visual analogue scale data. We aimed to test that design using time trade-off (TTO) data.

METHOD

We collected TTO values utilizing EQ-VT, orthogonal, and D-efficient designs. The EQ-VT design included 86 health states distributed over 3 blocks of 30 states with some duplicates. The orthogonal and D-efficient designs each comprised 1 block of 30 states. A total of 525 university students were asked to value a random block of health states using EQ-PVT (a PowerPoint replica of EQ-VT software), which generated 100 observations per health state in all 3 designs. We modeled data by design and compared the root mean square error (RMSE) between observed and predicted values within and across the designs.

RESULTS

The EQ-VT design had the lowest RMSE of 0.052; the RMSEs for the orthogonal and the D-efficient designs were 0.066 and 0.063, respectively. RMSE results between designs differed for more severe health states. Some coefficients differed between designs.

CONCLUSION

Smaller designs did not lead to significant increases in prediction errors when modeling TTO data (measuring 0.01 on a utility scale). Resource-constrained countries may use small designs for valuation studies, especially when other types of preference data, such as those from discrete choice experiments, are collected and modeled jointly.

Burden of visual impairment associated with eye diseases: exploratory survey of 298 Chinese patients

OBJECTIVES

To explore the economic burden, prevalence of catastrophic healthcare expenditure (CHE) and the quality of life (QoL) of Chinese patients with visual impairment (VI) associated with eye diseases.

DESIGN

A questionnaire survey from March to May 2016 by structured face-to-face interviews of patients with VI.

PARTICIPANTS

302 patients who were diagnosed with moderate VI or worse in both eyes (visual acuity <6/18) were included, and 298 patients (98.7%) who completed the survey questionnaires were eligible for the study.

OUTCOME MEASURES

The economic burden was estimated by calculating participants' direct costs covered in 2015 and the definition of CHE was out-of-pocket (OOP) costs exceeding 30% of annual household income. QoL was weighed by health utility value using time-trade-off valuation techniques.

RESULTS

Annual average direct costs per patient caused by VI were US$6988.6±US$10 834.3, and 70.3% were direct medical costs of which only 26.9% were reimbursable by medical insurance. 32.2% of households that suffered from CHE, in particular, were less wealthy patients with VI living in rural areas and without medical insurance. The health utility value was rated at 0.65 on average, and patients with VI aged 51-57, living alone and insured by commercial medical insurance had relatively less QoL.

CONCLUSION

Our study explored the economic burden and QoL of VI associated with patients with eye diseases in China, indicating a substantial economic burden and poor QoL. Preferential medical insurance policies should be designed in relation to people with VI to further reduce the health inequalities, avoid CHE and promote QoL.

Valuation of EQ-5D-5L Health States in Poland: the First EQ-VT-Based Study in Central and Eastern Europe

OBJECTIVE

Cost-utility analyses are becoming increasingly important in Central and Eastern Europe. We aimed to develop a Polish utility tariff for EQ-5D-5L health states.

METHODS

Face-to-face, computer-assisted interviews were collected in a representative sample. Each respondent followed a standardised protocol to collect ten composite time trade-off and seven discrete choice experiment observations. In the Bayesian approach, several model specifications were compared based on model fit, the usability of the final value set and how they reflect the elicitation procedure (e.g. censoring). A hybrid approach (using composite time trade-off and discrete choice experiment data) was employed in the final set, which was compared with the existing ones: EQ-5D-3L and EQ-5D-5L cross-walk.

RESULTS

Data from 1252 respondents (11,480 composite time trade-off valuations and 8764 discrete choice experiment pairs) were collected over the period June to October 2016. The final model accounted for random parameters, error scaling with fat tails, censoring at - 1, unwillingness to trade in time trade-off by the religious people and Cauchy distribution in discrete choice experiments. Pain/discomfort impacts the utility most: the disutility equals 0.575 when at level 5. In the value set, 4.4% of EQ-5D-5L states are worse than dead. The new value set has a comparable range (minimum of - 0.590 compared to - 0.523) and the same ordering of the first three dimensions (pain/discomfort, mobility, self-care) as the EQ-5D-3L value set and the EQ-5D-5L cross-walk value set. Moreover, it is more sensitive to a moderate decline in health.

CONCLUSIONS

The new value set supports consistency with past decisions in cost-utility studies, while offering a better assessment of even moderate improvements in health. It could represent an option for Central and Eastern Europe countries lacking their own value sets.

How Prevalent Are Implausible EQ-5D-5L Health States and How Do They Affect Valuation? A Study Combining Quantitative and Qualitative Evidence

BACKGROUND

When designing a valuation study, a criterion that has been used for selecting health states for direct valuation is whether the health states are plausible for respondents, because it is assumed that inclusion of implausible states would compromise data quality.

OBJECTIVES

To understand which health states are implausible, and how their values differ from the values of the plausible counterparts.

METHODS

One thousand six hundred Chinese students valued all 3125 health states of the 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) using the EuroQol visual analogue scale. Of these, 890 students also indicated whether each valued state was implausible or not using a binary scale. Additional qualitative interviews were conducted concerning the thought processes involved in the valuation of implausible states. We calculated an implausible score for each state. Then we examined the effect of implausibility on visual analogue scale values by fitting 2 regression models. Two independent researchers analyzed the qualitative transcripts using thematic analysis.

RESULTS

Approximately 30% of the EQ-5D-5L health states were rated as implausible by at least 50% of the respondents, but there was substantial heterogeneity in views about the plausibility of EQ-5D-5L states. Health states with dimensions that conflicted were more likely to be judged as implausible states. Health states that respondents deemed as implausible were more difficult to value and had lower values.

CONCLUSIONS

When respondents found the EQ-5D states to be implausible, they tended to give them lower values. Nevertheless, completely excluding implausible states from a valuation study is not possible because there is a lack of agreement among respondents on which states are implausible.

A hybrid modelling approach for eliciting health state preferences: the Portuguese EQ-5D-5L value set

BACKGROUND

The EQ-5D is a generic preference-based quality of life measure considered useful for supporting clinical and policy decisions by providing utility values that can easily be converted into quality-adjusted life years to be integrated in cost-utility economic evaluations. Although the three-level classification system of the EuroQol questionnaire (EQ-5D-3L) is still the most popular preference-based instrument used worldwide, several studies reported a ceiling effect on this version, especially in healthy and/or young individuals. In 2009, the EuroQol Group introduced a five-level EQ-5D, which expands the descriptive system from three to five levels within the same five dimensions. For this version to be used in health economic evaluation, societal values need to be assigned to the 3125 health states generated by this instrument.

OBJECTIVES

The aims of this study were to elicit the EQ-5D-5L health state preferences from the general Portuguese population and to derive the Portuguese value set for the EQ-5D-5L.

METHODS

A representative sample of the Portuguese general population aged above 18 years was stratified by age and gender (n = 1451). Between October 2015 and July 2016, 28 interviewers carried out a series of 1-h-long computer-assisted personal interviews following the EuroQol Valuation Technology protocol. Each interview included the valuation of ten health states using the composite time trade-off (cTTO) and seven pairs of discrete choice experiments (DCEs). A standardized tool for quality control was used to assess the quality of the data as well as direct supervision and cross-examination of 10% of the global sample size. Data from both cTTO and DCE valuation tasks were modelled using a censored heteroskedastic hybrid model.

RESULTS

Interviewers complied with the quality control protocol in providing high-quality valuation data. The hybrid econometric model had consistent and significant parameters. The derived societal values for the Portuguese population ranged from - 0.603 to 1.

CONCLUSION

This study provided the Portuguese value set for the EQ-5D-5L on the basis of a hybrid econometric model using cTTO and DCE data. These results represent the preferences of the Portuguese population and are recommended to inform health decision-making in Portugal.

Exploring the Impact of Adding a Respiratory Dimension to the EQ-5D-5L

Objectives. To evaluate the impact of adding a respiratory dimension (a bolt-on dimension) to the EQ-5D-5L health state valuations. Methods. Based on extensive regression and principal component analyses, 2 respiratory bolt-on candidates were formulated: R1, limitations in physical activities due to shortness of breath, and R2, breathing problems. Valuation interviews for the selected bolt-ons were performed with a representative sample from the Dutch general public using the standardized interview protocol and software of the EuroQol group. Hybrid models based on the combined time-tradeoff (TTO) and discrete choice experiment (DCE) data were estimated to assess whether the 5 levels of the respiratory bolt-on led to significant changes in utility values. Results. For each bolt-on candidate, slightly more than 200 valuation interviews were conducted. Mean TTO values and DCE choice probabilities for health states with a level 4 or 5 for the respiratory dimension were significantly lower compared with the same health states in the Dutch EQ-5D-5L valuation study without the respiratory dimension. Results of hybrid models showed that for the bolt-on “limitations in physical activities,” the utility decrements were significant for level 3 (–0.055), level 4 (–0.087), and level 5 (–0.135). For “breathing problems,” the utility decrements for the same levels were greater (–0.086, –0.219, and –0.327, respectively). Conclusions. The addition of each of the 2 respiratory bolt-ons to the EQ-5D-5L had a significant effect on the valuation of health states with severe levels for the bolt-on. The bolt-on dimension “breathing problems” showed the greatest utility decrements and therefore seems the most appropriate respiratory bolt-on dimension.

EQ-5D-5L Valuation for the Malaysian Population

OBJECTIVES

The aim of this study was to develop an EQ-5D-5L value set reflecting the health preferences of the Malaysian adult population.

METHODS

Respondents were sampled with quotas for urbanicity, gender, age, and ethnicity to ensure representativeness of the Malaysian population. The study was conducted using a standardized protocol involving the EuroQol Valuation Technology (EQ-VT) computer-assisted interview system. Respondents were administered ten composite time trade-off (C-TTO) tasks and seven discrete choice experiment (DCE) tasks. Both linear main effects and constrained non-linear regression models of C-TTO-only data and hybrid models combining C-TTO and DCE data were explored to determine an efficient and informative model for value set prediction.

RESULTS

Data from 1125 respondents representative of the Malaysian population were included in the analysis. Logical consistency was present in all models tested. Using cross-validation, eight-parameter models for C-TTO only and C-TTO + DCE hybrid data displayed greater out-of-sample predictive accuracy than their 20-parameter, main-effect counterparts. The hybrid eight-parameter model was chosen to represent the Malaysian value set, as it displayed greater out-of-sample predictive accuracy over C-TTO data than the C-TTO-only model, and produced more precise estimates. The estimated value set ranged from - 0.442 to 1.

CONCLUSIONS

The constrained eight-parameter hybrid model demonstrated the best potential in representing the Malaysian value set. The presence of the Malaysian EQ-5D-5L value set will facilitate its application in research and health technology assessment activities.

Conducting a Time Trade-Off Study Alongside a Clinical Trial: A Case Study and Recommendations

Time trade-off (TTO) is an established method in health economics to elicit and value individuals' preferences for different health states. These preferences are expressed in the form of health-state utilities that are typically used to measure health-related quality of life and calculate quality-adjusted life-years in an economic evaluation. The TTO approach to directly elicit health-state utilities is particularly valuable when generic instruments (e.g. EQ-5D) may not fully capture changes in utility in a clinical trial. However, there is limited guidance on how a TTO study should be conducted alongside a clinical trial despite it being a valuable tool. We present an account of the design and development of a TTO study within a clinical trial as a case study. We describe the development of materials needed for the TTO interviews, the piloting of the TTO materials and interview process, and recommendations for future TTO studies. This paper provides a practical guide and reference for future applications of the TTO method alongside a clinical trial.

Valuation of Health States Considered to Be Worse Than Death-An Analysis of Composite Time Trade-Off Data From 5 EQ-5D-5L Valuation Studies

OBJECTIVES

To evaluate the discriminative ability of negative values measured in 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) value set studies.

METHODS

This is a secondary analysis of EQ-5D-5L value set studies from Singapore, the Netherlands, China, Thailand, and Canada in which health state values were elicited from a general population sample using a composite time trade-off (TTO) method. Mean values were calculated for health states with same severity. The association between the mean values and severity was evaluated using Pearson correlation (r). A linear mixed model using severity as the fixed effect was fitted for values. The analyses were performed separately for positive values (from a conventional TTO for health states considered "better than death") and negative values (from a lead time TTO for health states considered "worse than death").

RESULTS

In Singapore (N = 1000; negative values 32.6%), the mean decreased with severity from 0.89 to 0.21 for positive values and increased with severity from -0.98 to -0.89 for negative values. The correlation between values and severity was much lower for negative values (r = -0.016) than for positive values (r = -0.614). The coefficient of severity in the linear mixed model for negative values was much smaller (coefficient = -0.009; pseudo-R² < 0.001) compared with the model for positive values (coefficient = -0.041; pseudo-R² = 0.337). Results using data sets from the other countries were similar.

CONCLUSIONS

Negative values are not associated with severity of health states in EQ-5D-5L valuation studies, suggesting poor discriminative ability of the lead time TTO method in valuing health states considered worse than death.

Health utilities in cancer patients: A study protocol for a prospective, longitudinal cohort using online survey

BACKGROUND

Cost-utility analysis (CUA) is becoming more commonly used in healthcare decision-making. CUA uses the quality-adjusted life-years (QALY) metric, which combines the length of life with the health-related quality of life (HRQoL). Most QALY-measuring instruments were validated for general populations. For patients with cancer, the perception of their health state is different and may vary by the type of cancer considered. In Quebec, no preference weights for QALY have been developed, neither for the general population nor particular subpopulations.

METHODS/DESIGN

This survey is a prospective, longitudinal cohort study. The study objectives are: to assess the extent of difference in health utilities between the general population and patients with breast or colorectal cancer; to develop a QALY preference weights dataset for patients with cancer; and to perform "mapping" with different HRQoL questionnaires by correlating the SF-6Dv2 with the EQ-5D-5L, European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30, and functional assessment of cancer therapy - general questionnaires. Data will be collected via a self-administered online survey. Patients' health utilities will be measured within 2 days before the beginning of a chemotherapy treatment cycle and about 8 days after the start of the chemotherapy. Health utilities will be measured by a hybrid method using the time-trade-off and discrete choice experiment methods.

ETHICS AND DISSEMINATION

The proposed research was reviewed and approved by the Institutional Research Ethics Review Boards of the CHUS. We will disseminate our study findings through peer-reviewed publications and conference presentations.

Choice Defines QALYs: A US Valuation of the EQ-5D-5L

BACKGROUND

The 5-level version of the EQ-5D (EQ-5D-5L) was introduced as an improvement on the original 3-level version (EQ-5D-3L). To date, 6 country-specific value sets have been published for EQ-5D-5L and 9 US value sets have been published for other instruments. Our aims were to (1) produce EQ-5D-5L values on a quality-adjusted life year (QALY) scale from the perspective of US adults and (2) compare them with US EQ-5D-3L values and the other country-specific EQ-5D-5L values.

METHODS

In 2016, 8222 US respondents from all 50 states and Washington, DC completed an online survey including a discrete choice experiment with 20 paired comparisons. Each comparison asked respondents, "Which do you prefer?" regarding a pair of alternatives described using EQ-5D-5L and lifespan attributes. On the basis of more than 50 choices on each of the 3160 pairs, we estimated EQ-5D-5L values on a QALY scale and compared them with the US EQ-5D-3L values and the other country-specific EQ-5D-5L values.

RESULTS

Ranging from -0.287 (55555) to 0.992 (11121) on a QALY scale, the estimated EQ-5D-5L values were similar to the US EQ-5D-3L values. Compared with the US EQ-5D-3L values, the values exhibited greater sensitivity and specificity and higher correlation with the EQ-5D-5L values of other countries, particularly England.

CONCLUSIONS

Like previous US valuation studies, this study produced nationally representative EQ-5D-5L values on a QALY scale. The results further demonstrate the advantages of the EQ-5D-5L over its 3-level predecessor as a preference-based summary measure of health-related quality of life from the perspective of US adults.

Health State Utilities for Acute Myeloid Leukaemia: A Time Trade-off Study

OBJECTIVES

Acute myeloid leukaemia (AML) is an aggressive haematological cancer associated with significant humanistic impact. The current study assessed how the general public in the United Kingdom (UK) values AML health states.

METHODS

The composite time trade-off (cTTO) methodology was employed to elicit health state utilities in AML. Pertinent AML literature related to symptom and quality-of-life impact including physical, functional and emotional well-being, as well as the safety profile of AML treatments, were taken into consideration for drafting health state descriptions. Ten health states included in the study were newly diagnosed AML, induction, consolidation, maintenance, long-term follow-up, relapsed/refractory, stem-cell transplant (SCT) procedure, SCT recovery, SCT long-term follow-up with complications and SCT long-term follow-up without complications. The descriptions were validated by haematologists and nurse specialists for clinical accuracy and completeness. A total of 210 individuals from the general UK population participated in the cTTO interviews. Descriptive statistics were computed for health state utility values.

RESULTS

The mean age of the participants was 44.0 years (standard deviation [SD] 14.9, range 18-81) and comprised 129 (61.4%) female participants. The utility values ranged from 0.94 (SD 0.13) for SCT long-term follow-up without complications to - 0.21 (SD 0.62) for the SCT procedure.

CONCLUSIONS

The study provides health utilities for a range of AML health states, with the SCT procedure health state being valued worse than death. The utilities obtained in this study can be employed as inputs in cost-effectiveness analyses of AML therapies.

Overview, Update, and Lessons Learned From the International EQ-5D-5L Valuation Work: Version 2 of the EQ-5D-5L Valuation Protocol

A standardized 5-level EuroQol 5-dimensional questionnaire (EQ-5D-5L) valuation protocol was first used in national studies in the period 2012 to 2013. A set of problems encountered in this initial wave of valuation studies led to the subsequent refinement of the valuation protocol. To clarify lessons learned and how the protocol was updated when moving from version 1.0 to the current version 2.1 and 2.0, this article will (1) present the challenges faced in EQ-5D-5L valuation since 2012 and how these were resolved and (2) describe in depth a set of new challenges that have become central in currently ongoing research on how EQ-5D-5L health states should be valued and modeled.

Effect of Health State Sampling Methods on Model Predictions of EQ-5D-5L Values: Small Designs Can Suffice

OBJECTIVE

The current five-level EQ-5D (EQ-5D-5L) valuation protocol requires the valuation of 86 states. It has been demonstrated that the selection of empirically valued health states affects the extrapolated values in three-level EQ-5D (EQ-3D-3L). In this investigation, we aim to compare the performance of the current EQ-5D-5L valuation design with other designs.

STUDY DESIGN

1603 university students participated in a valuation study using a visual analog scale (VAS) to produce values for all EQ-5D-5L states. Different designs were generated to test their prediction accuracy.

METHODS

Subsamples of the dataset were used to mimic data obtained from a particular design; the remaining dataset was used as the validation set. In addition to EuroQol Group Valuation Technology (EQ-VT) design, alternative subsamples and designs were created using random, orthogonal, and "optimizing D-efficiency" sampling methods. The root mean squared error (RMSE) was used as the measure of prediction accuracy.

RESULTS

The EuroQol Group Valuation Technology (EQ-VT) design showed an average RMSE of 3.44 on EQ-VAS, for all 3125 health states combined. Notably, a 25-state orthogonal design performed similarly to the EQ-VT design, with a smaller RMSE of 3.40, and was thus the most efficient design. One caveat with respect to the orthogonal design was that it did not predict the mild states well.

CONCLUSIONS

Our study supports the EQ-VT design. Smaller designs were identified with similar overall prediction accuracy. It is worth investigating whether issues with misprediction of mild states can be resolved, as the use of smaller size designs would reduce the cost of the valuation of EQ-5D-5L considerably.

Valuation of the EQ-5D-5L in Taiwan

OBJECTIVES

To date, a value set for the EQ-5D-5L based on the health state preferences of the general Taiwanese population has not been available. This study aimed to develop a Taiwanese value set for EQ-5D-5L to facilitate health technology assessment for medical products and services.

METHODS

An international standardized protocol for EQ-5D-5L valuation studies developed by the EuroQol group was adopted. Adult members of the general public were recruited from six geographic regions in Taiwan. In computer-based face-to-face interviews, each participant completed 10 composite time trade-off (C-TTO) tasks and 7 discrete choice experiment (DCE) tasks. The C-TTO and DCE data were modeled alone or in combination (using hybrid models) with additive models containing 20 dummy variables as main effects. The model performance was assessed both quantitatively and qualitatively (mainly logical consistency and prediction patterns).

RESULTS

Of 1,073 recruited participants, 1,000 completed the study. Approximately 13% of observed utility values were -1 in the C-TTO tasks. The hybrid model, using all available data that assumed C-TTO response values left-censored at -1 and with main effects coefficients with logical consistency (monotonicity), was considered as the most appropriate model. The predicted utility ranged from -1.0259 to 1.

CONCLUSIONS

An EQ-5D-5L value set was developed for Taiwan using an established study protocol and a representative sample of the general population. This may facilitate health economic evaluations and decision making on resource allocation under Taiwan's national health insurance program in the future.

Cast versus functional brace in the rehabilitation of patients treated for an ankle fracture: protocol for the UK study of ankle injury rehabilitation (AIR) multicentre randomised trial

INTRODUCTION

Each year in the UK over 120 000 people fracture their ankle. It is not known what the best rehabilitation strategy is for these people. Traditionally standard care has involved immobilisation in a plaster cast but an alternative is a functional brace, which can be removed to allow early movement. This paper details the protocol for a multicentre randomised trial of plaster cast immobilisation versus functional bracing for patients with an ankle fracture.

METHODS AND ANALYSIS

We will recruit adults with a fractured ankle, for which the treating clinician would consider plaster cast to be a reasonable management option. Randomisation will be on a 1:1 basis, stratified by centre, operative or non-operative management and age. Participants will be allocated to either plaster cast or a functional brace, both treatments are widely used. To have 90% power to detect a difference of 10 points on the primary outcome (Olerud and Molander Ankle Score) at the primary outcome time point (16 weeks), we need to randomise a minimum of 478 people. Quality of life and resource use will be collected at 6, 10, 16, 24 weeks and 12, 18, 24 months. The differences between treatment groups will be assessed on an intention-to-treat basis. The economic evaluation will adhere to the recommendations of the National Institute for Health and Care Excellence reference case.

ETHICS, REGISTRATION AND DISSEMINATION

National Research Ethic Committee approved this study on 4 July 2017 (17/WM/0239). The first site opened to recruitment 9 October 2017. The results of this trial will be submitted to a peer-reviewed journal and will inform clinical practice.

TRIAL REGISTRATION NUMBER

ISRCTN15537280; Pre-results.

Valuation of EQ-5D-5L health states: a comparison of seven Asian populations

Objectives: To compare the time trade-off (TTO) utility values of EQ-5D-5L health states elicited from different general populations in Asia. Methods: We analyzed the TTO data from seven Asian EQ-5D-5L valuation studies in which utility values of 86 EQ-5D-5L health states were elicited from general population samples. An eight-parameter multiplicative regression model including five dimension parameters (mobility [MO], self-care, usual activities [UA], pain/discomfort, anxiety/depression) and three level parameters (level 2 [L2], level 3 [L3], and level 4 [L4]) was used to model the data from each of the populations. The model coefficients were compared to understand how the valuations of EQ-5D-5L health states differ. Results: For dimension parameters, Korea and Indonesia generally had the highest and lowest values among the populations, respectively; UA and MO commonly had the highest and lowest values among the parameters, respectively. For level parameters, Singapore and Korea generally had the highest and lowest values, respectively; L2 showed less variance compared to L3 and L4. Koreans, Indonesians, and Singaporeans appeared to have different health preferences compared with other populations. Conclusion: Utility values of EQ-5D-5L health states differ among Asian populations, suggesting that each health system should establish and use its own value set.

EQ-5D-5L norms for the urban Chinese population in China

BACKGROUND

To generate Chinese population norms for the EQ-5D-5L dimensions, EQ-VAS (Visual Analogue Scale) scores and EQ-5D-5L index scores, stratified by gender and age. The EQ-5D is a widely used generic health-related quality of life instrument to describe population health and health outcomes in clinical trials and health economic evaluations. Currently, there are no EQ-5D-5L population norms for China.

METHODS

This norm study utilized the data collected in an EQ-5D-5L valuation study in China between December 2012 and January 2013. In the valuation study, respondents were asked to report their own health states using the EQ-5D-5L descriptive system and the EQ-VAS. Respondents' demographic information was also collected. The EQ index score was calculated using the EQ-5D-5L value set based on the Chinese urban population. Norm scores were reported by important demographic variables.

RESULTS

The mean EQ-VAS scores ranged between 88.3 for males of < 19 years and 82.9 for females of 60-69 years. Contrary to other population studies, females reported higher EQ-VAS scores than males in every age group except for 20-29 years. The mean EQ-5D-5L index values ranged from 0.912 for females of > 70 years to 0.971 for females of 30-39 years. Respondents reported more problems in the dimensions 'pain/discomfort' and 'anxiety/depression' than in the dimensions 'mobility', 'self-care' and 'usual activities' in all age groups.

CONCLUSIONS

The population norm scores for the EQ-5D can be used as reference values for comparative purposes in future Chinese studies. Further research into rural and/or a more representative population is warranted.

Experience-Based Values: A Framework for Classifying Different Types of Experience in Health Valuation Research

Whether health values should be elicited from the perspective of patients or the general public is still an open debate. The overall aim of this paper is to increase knowledge on the role of experience in health preference-based valuation research. The objectives of this paper are threefold. First, we elaborate the idea of experience-based (EB) values under the informed value or knowledge viewpoint. We think the whole scope of knowledge about the health states involved in valuation exercises is not fully integrated in the previous literature. For instance, personal knowledge based on past experiences, contemplating the health state as a likely future condition, knowing someone who is currently experiencing the state, or just receiving detailed information about the health states; all these situations capture different nuances of health-related experience which are not explicitly referred to in valuation tasks. Second, we propose a framework where the extended factor of experience is detached from other factors interwoven into the valuation exercise. Third, we examine how experience is tackled in different value sets (EB or non-EB) identified via a literature review. We identified the following elements (and items) in a value set: health state (without description, described using a multi-attribute instrument, described using other method), reference person (the respondent; other person, similar/known/hypothetical), time frame (past, present, future), raters (public, representative/convenience; vested interest, patients/other) and experience (personal experience, past/present/future; vicarious experience, affective/non-affective; no experience). Forty-nine valuation exercises were extracted from 22 reviewed papers and classified following our suggested set of elements and items. The results show that the role of experience reported in health valuation-related papers is frequently disregarded or, at most, minimised to the item of personal experience (present)-linked to self-reported health.