Accounting for Unobservable Preference Heterogeneity and Evaluating Alternative Anchoring Approaches to Estimate Country-Specific EQ-5D-Y Value Sets: A Case Study Using Spanish Preference Data

An Acquired Taste: Latent Class Analysis to Compare Adolescent and Adult Preferences for EQ-5D-Y-3L Health States

OBJECTIVES

US stakeholders advised including adolescents in the valuation study for the EQ-5D-Y-3L, a step toward greater acknowledgment of children in informing societal values. This study aimed to assess the relative contribution of adolescent and adult preferences to a model when combined.

METHODS

Discrete choice experiment data were collected from an online sample of 1529 adults and 714 adolescents (ages 11-17). Each respondent completed 15 discrete choice experiment tasks, which were analyzed using latent class models representing varying number of preference classes. Within the best-fitting model, the contribution of each class was determined by the scale-adjusted class share (SACS), combining the class's proportion of respondents (class share) and the magnitude of coefficients (within-class scale). We estimated the contribution of adolescent and adult respondents to SACS for each class, with lower SACS representing less contribution to the combined model.

RESULTS

The best-fitting model described 6 classes. Adults had higher contribution to all except 1 class, accounting for 78.7% of the total contribution. After adjusting for the unequal sample size of adolescent and adult respondents, adults contributed approximately 65.0%, and adolescents contributed 35.0% of the weights toward a combined model.

CONCLUSIONS

Adolescents showed diminished, disproportionate representation in a combined model, due in part to more indifferent, less informative preferences for EQ-5D-Y-3L health states compared with adults. Latent class analysis showcases one approach to estimate and weight contributions from intentionally sampled subgroups in a combined model.

Measurement Properties of the EQ-5D Instruments in Children and Adolescents: A Systematic Review

BACKGROUND

The EQ-5D instruments have been widely used to measure health-related quality of life (HRQoL) in child and adolescent populations, especially the EQ-5D-Y-3L and EQ-5D-Y-5L (beta version). Although not specifically designed for younger users, the adult versions (EQ-5D-3L and EQ-5D-5L) are also used in these populations. While the measurement properties of these instruments have been evaluated in children and adolescents, no systematic review to date has employed a rigorous method to assess risk of bias. Additionally, quality criteria for good measurement properties and certainty of evidence have not been thoroughly evaluated. The aim of this study was to summarize and critically appraise the evidence on the measurement properties of all EQ-5D instruments in children and adolescents.

METHODS

We conducted electronic searches on MEDLINE, EMBASE, CINAHL, EconLit, National Health Service Economic Evaluation Database (NHS-EED), and Health Technology Assessment (HTA) databases up to May 2024. We included studies measuring HRQoL using either the self-reported or proxy-reported version of the EQ-5D instruments-EQ-5D-3L, EQ-5D-5L, EQ-5D-Y-3L, and EQ-5D-Y-5L-using the descriptive system, visual analogue scale, and/or utility score in children and adolescents up to 19 years of age, and that tested at least one measurement property (e.g., reliability). The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) methodology was followed to assess risk of bias, to score results for measurement properties, and to perform an evidence synthesis using a modified Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) approach.

RESULTS

From 3586 records identified through the search, 65 studies were included in this systematic review. We found moderate certainty of evidence of sufficient comprehensibility and comprehensiveness of the EQ-5D-Y-3L and EQ-5D-Y-5L. Furthermore, we found very low certainty of evidence of inconsistent relevance for the EQ-5D-Y-3L, whereas the EQ-5D-Y-5L had sufficient relevance. Almost all the measurement properties (reliability, hypothesis testing for construct validity, and responsiveness) considering all the EQ-5D versions ranged from moderate certainty of evidence of insufficient results to very low certainty of evidence of insufficient results.

CONCLUSION

There is moderate certainty of evidence that the EQ-5D-Y-3L and EQ-5D-Y-5L have sufficient content validity. Both instruments can be recommended to measure HRQoL in children and adolescents aged 8-15 years. However, most of the measurement properties across all EQ-5D versions showed insufficient results, with certainty of evidence ranging from moderate to very low due to inconsistency and doubtful to inadequate risk of bias. Therefore, further research is needed to improve the methodological quality of studies on EQ-5D instruments for children and adolescents.

SYSTEMATIC REVIEW REGISTRATION

International prospective register of systematic reviews (PROSPERO): CRD42020218382 and Open Science Framework: https://osf.io/r8kt9/ .

Comparison of EQ-5D-Y-3L Utility Scores Using Nine Country-Specific Value Sets in Chinese Adolescents

OBJECTIVE

This study aimed to assess and compare the measurement properties of EQ-5D-Y-3L utilities derived from available countries' value sets (Chinese, Japanese, Slovenian, German, Spanish, Hungarian, Netherlandish, Belgian, and Indonesian), among Chinese adolescents.

METHODS

From July to September 2021, a large-scale cross-sectional survey was administered across 16 cities in Shandong, China, with the objective of assessing the health status of junior high school students aged 10-18 years. Supported by the educational authorities, quick response (QR) codes and questionnaire links were disseminated to schools. A total of 97,413 junior high school students completed the questionnaire. Agreement, convergent validity, and known-group validity were determined in the nine country-specific value sets.

RESULTS

The Indonesian value set demonstrated the highest mean health utility score (0.970), followed by the Japanese (0.961), Chinese (0.960), Netherlandish (0.948), Hungarian (0.942), German (0.938), Belgian (0.932), Slovenian (0.926), and Spanish (0.926) value sets, respectively. The utility scores derived from Asian value sets were higher than those from Europe. Good or excellent agreements (intraclass correlation coefficients > 0.7) were found between each paired value set. In Bland-Altman plots, the 95% limits of agreement for any two value sets were 0.046-0.348. A strong relationship (Spearman's correlation coefficients > 0.99) between any two value sets was found. The EQ-5D-Y-3L utility scores discriminated equally well for the nine value sets across three known groups. The effect size and the relative efficiency statistics showed the Chinese value sets were more sensitive in general. Referring to the Chinese value set, all the relative efficiency values in each value set were similar across three known groups, ranging from 0.9 to 1.0.

CONCLUSIONS

A total of nine country-specific EQ-5D-Y-3L value sets showed an overall high level of agreement, strong correlation, and good known-group validity. However, the utility scores derived from nine EQ-5D-Y-3L value sets were different and the country-specific value sets were not interchangeable.

Nature-based interventions for individuals with rare skeletal disorders: evaluation of a 5-day sailing program on health-related quality of life

Individuals with rare skeletal disorders like Multiple Osteochondromas and Ollier Disease often experience physical and psychological burdens. Adventure therapy, with activities like sailing in outdoor settings, promotes personal growth and psychological well-being, potentially improving health-related quality of life (HRQoL). This study aimed to evaluate the impact of a sailing program on health-related quality of life and participant satisfaction in individuals with Multiple Osteochondromas and Ollier Disease. A quasi-experimental one-group pre-post design was employed, with HRQoL assessed using the EQ-5D® instrument and participant satisfaction measured via a feedback survey. Data were collected before and after the five-day sailing program conducted in the Mediterranean Sea in 2022 and 2023, involving participants diagnosed with Multiple Osteochondromas and Ollier Disease. Statistical analyses were performed using the Wilcoxon signed-rank test and McNemar's test for paired data. A significance level of p < 0.05 and p < 0.10 was considered. A total of 25 participants, predominantly male (52%), with a median age of 16 years (ranking from 11 to 31), were included in the study. The sailing program had mixed impact on HRQoL. Specifically, individuals who were female (p = 0.03), aged 16 and older (p = 0.04), with higher educational attainment (p = 0.10) or stronger self-management (p = 0.09), resilience (p = 0.01) and self-engagement (p = 0.09) skills experienced enhanced HRQoL. Conversely, other participants exhibited an increase in self-care difficulties (p = 0.02) and a trend towards worsening pain/discomfort (p = 0.38). Overall satisfaction with the program was high, with 90% of participants expressing satisfaction.This is the first study which examined HRQoL in Multiple Osteochondromas and Ollier Disease patients within an outdoor adventure therapy setting. Findings suggest that adventure therapy, integrated into healthcare strategies, may offer a valuable complement to conventional treatments for rare skeletal disorders. Future research, including randomized controlled trials, are necessary to confirm these results and develop robust interventions for improving the well-being in this population.

Comparison of cognitive behaviour therapy versus activity management, both delivered remotely, to treat paediatric chronic fatigue syndrome/myalgic encephalomyelitis: the UK FITNET-NHS RCT

Design

Parallel-group randomised controlled trial.

Methods

Adolescents aged 11-17 years, diagnosed with myalgic encephalomyelitis/chronic fatigue syndrome and with no local specialist treatment centre, were referred to a specialist service in South West England.

Interventions

Fatigue In Teenagers on the interNET in the National Health Service is a web-based myalgic encephalomyelitis/chronic fatigue syndrome-focused cognitive-behavioural therapy programme for adolescents, supported by individualised written, asynchronous electronic consultations with a clinical psychologist/cognitive-behavioural therapy practitioner. The comparator was videocall-delivered activity management with a myalgic encephalomyelitis/chronic fatigue syndrome clinician. Both treatments were intended to last 6 months.

Objectives

Estimate the effectiveness of Fatigue In Teenagers on the interNET in the National Health Service compared to Activity Management for paediatric myalgic encephalomyelitis/chronic fatigue syndrome. Estimate the effectiveness of Fatigue In Teenagers on the interNET in the National Health Service compared to Activity Management for those with mild/moderate comorbid mood disorders. From a National Health Service perspective, estimate the cost-effectiveness of Fatigue In Teenagers on the interNET in the National Health Service compared to Activity Management over a 12-month horizon.

Primary Outcome

36-item Short Form Health Survey Physical Function subscale at 6 months post randomisation.

Randomisation

Web-based, using minimisation with a random component to balance allocated groups by age and gender.

Blinding

While the investigators were blinded to group assignment, this was not possible for participants, parents/carers and therapists.

Results

The treatment of 314 adolescents was randomly allocated, 155 to Fatigue In Teenagers on the interNET in the National Health Service. Mean age was 14 years old and 63% were female.

Primary outcome

At 6 months, participants allocated to Fatigue In Teenagers on the interNET in the National Health Service were more likely to have improved physical function (mean 60.5, standard deviation 29.5, n = 127) compared to Activity Management (mean 50.3, standard deviation 26.5, n = 138). The mean difference was 8.2 (95% confidence interval 2.7 to 13.6, p = 0.003). The result was similar for participants meeting the National Institute for Health and Care Excellence 2021 diagnostic criteria.

Secondary outcomes

Fatigue In Teenagers on the interNET in the National Health Service participants attended, on average, half a day more school per week at 6 months than those allocated Activity Management, and this difference was maintained at 12 months. There was no strong evidence that comorbid mood disorder impacted upon the relative effectiveness of the two interventions. Similar improvement was seen in the two groups for pain and the Clinical Global Impression scale, with a mixed picture for fatigue. Both groups continued to improve, and no clear difference in physical function remained at 12 months [difference in means 4.4 (95% confidence interval -1.7 to 10.5)]. One or more of the pre-defined measures of a worsening condition in participants during treatment, combining therapist and patient reports, were met by 39 (25%) participants in the Fatigue In Teenagers on the interNET in the National Health Service group and 42 (26%) participants in the Activity Management group. A small gain was observed for the Fatigue In Teenagers on the interNET in the National Health Service group compared to Activity Management in quality-adjusted life-years (0.002, 95% confidence interval -0.041 to 0.045). From an National Health Service perspective, the costs were £1047.51 greater in the Fatigue In Teenagers on the interNET in the National Health Service group (95% confidence interval £624.61 to £1470.41). At a base cost-effectiveness threshold of £20,000 per quality-adjusted life-year, the incremental cost-effectiveness ratio was £457,721 with incremental net benefit of -£1001 (95% confidence interval -£2041 to £38).

Conclusion

At 6 months post randomisation, compared with Activity Management, Fatigue In Teenagers on the interNET in the National Health Service improved physical function and school attendance. The additional cost of Fatigue In Teenagers on the interNET in the National Health Service and limited sustained impact mean it is unlikely to be cost-effective.

Trial registration

This trial is registered as ISRCTN18020851.

Funding

This award was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme (NIHR award ref: 14/192/109) and is published in full in Health Technology Assessment; Vol. 28, No. 70. See the NIHR Funding and Awards website for further award information.

Estimating an EQ-5D-Y-3L Value Set for Brazil

INTRODUCTION

The EQ-5D-Y-3L is a generic measure of health-related quality of life in children and adolescents. Although the Brazilian-Portuguese EQ-5D-Y-3L version is available, there is no value set for it, hampering its use in economic evaluations. This study aimed to elicit a Brazilian EQ-5D-Y-3L value set based on preferences of the general adult population.

METHODS

Two independent samples of adults participated in an online discrete choice experiment (DCE) survey and a composite time trade-off (cTTO) face-to-face interview. The framing was "considering your views for a 10-year-old child". DCE data were analyzed using a mixed-logit model. The 243 DCE predicted values were mapped into the observed 28 cTTO values using linear and non-linear mapping approaches with and without intercept. Mapping approaches' performance was assessed to estimate the most valid method to rescale DCE predicted values using the model fit (R2), Akaike Information Criteria (AIC), root mean squared error (RMSE), and mean absolute error (MAE).

RESULTS

A representative sample of 1376 Brazilian adults participated (DCE, 1152; cTTO, 211). The linear mapping without intercept (R2 = 96%; AIC, - 44; RMSE, 0.0803; MAE, - 0.0479) outperformed the non-linear without intercept (R2 = 98%; AIC, - 63; RMSE, 0.1385; MAE, - 0.1320). Utilities ranged from 1 (full health) to - 0.0059 (the worst health state). Highest weights were assigned to having pain or discomfort (pain/discomfort), followed by walking about (mobility), looking after myself (self-care), doing usual activities (usual activities), and feeling worried, sad, or unhappy (anxiety/depression).

CONCLUSION

This study elicited the Brazilian EQ-5D-Y-3L value set using a mixed-logit DCE model with a power parameter based on a linear mapping without intercept, which can be used to estimate the quality-adjusted life-years for economic evaluations of health technologies targeting the Brazilian youth population.

Transitioning between the EQ-5D youth and adult descriptive systems in a group of adolescents

PURPOSE

To investigate whether the same health state results in the same distribution of responses on the EQ-5D youth and adult descriptive systems.

METHODS

Adolescents aged 13-18 years with a range of health conditions and from the general school going population were recruited in South Africa (ZA) and Ethiopia (ET). In ZA participants completed the English EQ-5D-3L, EQ-5D-Y-3L and EQ-5D-5L in parallel. Whereas in ET participants completed the Amharic EQ-5D-5L and EQ-5D-Y-5L in parallel. Analysis aimed to describe the transition between youth and adult instruments and not differences between countries.

RESULTS

Data from 592 adolescents completing the EQ-5D-3L, EQ-5D-Y-3L and EQ-5D-5L (ZA) and 693 completing the EQ-5D-5L and EQ-5D-Y-5L (ET) were analysed. Adolescents reported more problems on the youth versions compared to the adult version for the dimension of mental health. 13% and 4% of adolescents who reported no problems on the EQ-5D-3L and EQ-5D-5L reported some problems on the EQ-5D-Y-3L respectively. This was less notable with transition between the five level versions with 4% of adolescents reporting more problems on the EQ-5D-Y-5L than the EQ-5D-5L. Very few adolescents reported severe problems (level 3 on the EQ-5D-3L or EQ-5D-Y-3L and level 4 and level 5 on the EQ-5D-5L or EQ-5D-5L) thus there was little variation between responses between the versions. In ZA, discriminatory power, measured on the Shannon's Index, was higher for Y-3L compared to 3L for pain/discomfort (ΔH'=0.11) and anxiety/depression (ΔH'=0.04) and across all dimensions for Y-3L compared to 5L. Similarly, in ET discriminatory power was higher for Y-5L than 5L (ΔH' range 0.05-0.09). Gwet's AC showed good to very good agreement across all paired (ZA) 3L and (ET) 5L dimensions. The summary score of all EQ-5D versions were able to differentiate between known disease groups.

CONCLUSION

Despite the overall high levels of agreement between EQ-5D instruments for youth and for adults, they do not provide identical results in terms of health state, from the same respondent. The differences were most notable for anxiety/depression. These differences in the way individuals respond to the various descriptive systems need to be taken into consideration for descriptive analysis, when transitioning between instruments, and when comparing preference-weighted scores.

Health-related quality of life and associated risk factors in patients with Multiple Osteochondromas: a cross-sectional study

PURPOSE

To evaluate the health-related quality of life and associated risk factors for Multiple Osteochondromas patients.

METHODS

A cross-sectional, observational study was conducted from May to December 2022 during the routine visit to the referral center for rare skeletal disorders. All patients with Multiple Osteochondromas aged ≥ 3 years were included. EuroQol 5-dimension questionnaires, and demographic, clinical, and surgical history data were collected. Descriptive statistics, Fisher's exact test, One-sample t-test, Spearman's correlation, and multiple linear and logistic regression were performed to analyze the data. Results are reported following STROBE guidelines.

RESULTS

A total of 128 patients were included in the study, with a mean age of 14 [SD, 10] years. The mean EQ-5D Index Value was 0.863 [SD, 0.200] and the EQ-VAS was 84 [SD, 19] with a positive correlation between two scores [r = 0.541, p < 0.001]. Patients frequently referred problems in pain/discomfort [78.8%], anxiety/depression [50%], and usual activities [38.8%] dimensions. Increasing age was the common risk factor for health-related quality of life [p < 0.000], as well as Index Value and VAS scores were significantly lower in surgical patients [p = 0.001 and p < 0.001, respectively].

CONCLUSION

Increasing age and surgical procedures were found highly associated with reduced health-related quality of life in Multiple Osteochondromas patients. Our findings provide relevant information to support the establishment of patient-centered healthcare pathways and pave the way for further research into medical and non-medical therapeutic strategies for these patients.

Disease Burden, Clinical Outcomes, and Quality of Life in People with Hemophilia A without Inhibitors in Europe: Analyses from CHESS II/CHESS PAEDs

Introduction  Limited data relating to treatment burden, quality of life, and mental health burden of hemophilia A (HA) are currently available. Aim  To provide a comprehensive overview of unmet needs in people with HA (PwHA) using data generated from the Cost of Haemophilia in Europe: a Socioeconomic Survey-II (CHESS II) and CHESS in the pediatric population (CHESS PAEDs) studies. Methods  CHESS II and CHESS PAEDs are cross-sectional surveys of European males with HA or hemophilia B (HB) aged ≥18 and ≤17 years, respectively. Participants with FVIII inhibitors, mild HA, or HB were excluded from this analysis, plus those aged 18 to 19 years. Annualized bleeding rates (ABRs), target joints, and other patient-reported outcomes were evaluated. Results  Overall, 468 and 691 PwHA with available data for the outcomes of interest were stratified by hemophilia severity and treatment regimen in CHESS II and CHESS PAEDs, respectively. In these studies, 173 (37.0%) and 468 (67.7%) participants received FVIII prophylaxis, respectively; no participants received the FVIII mimetic emicizumab or gene therapy. ABRs of 2.38 to 4.88 were reported across disease severity and treatment subgroups in both studies. Target joints were present in 35.7 and 16.6% of participants in CHESS II and CHESS PAEDS; 43.8 and 23.0% had problem joints. Chronic pain was reported by a large proportion of PwHA (73.9% in CHESS II; 58.8% in CHESS PAEDs). Participants also reported low EQ-5D scores (compared with people without HA), anxiety, depression, and negative impacts on their lifestyles due to HA. Conclusions  These analyses suggest significant physical, social, and mental burdens of HA, irrespective of disease severity. Optimization of prophylactic treatment could help reduce the burden of HA on patients.

Using Age-Specific Values for Pediatric HRQoL in Cost-Effectiveness Analysis: Is There a Problem to Be Solved? If So, How?

Value sets for the EQ-5D-Y-3L published to date appear to have distinctive characteristics compared with value sets for corresponding adult instruments: in many cases, the value for the worst health state is higher and there are fewer values < 0. The aim of this paper is to consider how and why values for child and adult health differ; and what the implications of that are for the use of EQ-5D-Y-3L values in economic evaluations to inform healthcare resource allocation decisions. We posit four potential explanations for the differences in values: (a) The wording of severity labels may mean the worst problems on the EQ-5D-Y-3L are descriptively less severe than those on the EQ-5D-5L; (b) Adults may genuinely consider that children are less badly affected than adults by descriptively similar health issues. That is, for any given health problem, adult respondents in valuation studies consider children's overall health-related quality of life (HRQoL) on average to be higher than that for adults; (c) Values are being sought by eliciting adults' stated preferences for HRQoL in another person, rather than in themselves (regardless of whether the 'other person' concerned is a child); and (d) The need to elicit preferences for child HRQoL that are anchored at dead = 0 invokes special considerations regarding children's survival. Existing evidence does not rule out the possibility that (c) and (d) exert an upward bias in values. We consider the implications of that for the interpretation and use of values for pediatric HRQoL. Alternative methods for valuing children's HRQoL in a manner that is not 'age specific' are possible and may help to avoid issues of non-comparability. Use of these methods would place the onus on health technology assessment bodies to reflect any special considerations regarding child quality-adjusted life-year gains.

Whose Time Trade-Off Should Be Used? Anchoring Discrete Choice Experiment Latent Utilities in Health State Valuation

OBJECTIVES

To compare anchored discrete choice experiment (DCE) utility values using own versus others' time trade-off (TTO) responses in the valuation of SF-6Dv2.

METHODS

A representative sample of the general population was recruited in China. Through face-to-face interviews, both DCE and TTO data were collected from a randomly selected half of the respondents (own TTO sample), whereas only TTO data were collected from the other half (others' TTO sample). Conditional logit model was used to estimate DCE latent utilities. Three anchoring methods, including using the observed and the modeled TTO values for the worst state, and mapping DCE values onto TTO, were used to scale the latent utilities to health utilities. Prediction accuracy was assessed using intraclass correlation coefficient, mean absolute difference, and root mean squared difference compared with the mean observed TTO values between the anchoring results using the own versus others' TTO data.

RESULTS

Demographic characteristics were comparable between the own TTO sample (n = 252) and the others' TTO sample (n = 251). The mean (SD) observed TTO value for the worst state was -0.259 (0.591) for the own TTO sample and -0.236 (0.616) for the others' TTO sample. Anchoring DCE using own TTOs consistently showed a better prediction accuracy than using others' TTOs across the 3 anchoring methods in terms of the intraclass correlation coefficient (0.835-0.873 vs 0.771-0.804), mean absolute difference (0.127-0.181 vs 0.146-0.203), and root mean squared difference (0.164-0.237 vs 0.192-0.270).

CONCLUSION

When anchoring DCE-derived latent utilities onto the health utility scale, respondents' own TTO data would be preferred to TTO data obtained from a different sample.

Using Time Trade-Off Values to Estimate EQ-5D-Y Value Sets: An Exploratory Study

OBJECTIVES

The published international EQ-5D-Y-3L valuation protocol does not recommend the composite time trade-off (cTTO) method as the primary valuation method because of 2 major concerns. First, the cTTO method was shown to generate high values. Second, the cTTO method is not as feasible for valuing children's health as other established methods. This study aimed to explore the feasibility of using cTTO values alone to estimate EQ-5D-Y-3L value sets.

METHODS

We analyzed the cTTO data derived from the recently completed Chinese EQ-5D-Y-3L valuation study in which a total of 28 health states were valued. We assessed the feasibility of the cTTO tasks in terms of survey completion time and participant-reported difficulty of understanding the task, differentiating the health states, and deciding the answer. We also examined the data distribution characteristics and modeled the data using different models.

RESULTS

In total, 418 participants completed the cTTO interview. On average, participants took approximately 35.70 minutes (SD 12.42) to complete the interview and made 13.21 moves (SD 9.00) in the cTTO tasks. There were 74.16%, 59.33%, and 11.48% of participants indicated that it was easy to understand the cTTO tasks, easy to differentiate between the health states, and difficult to decide on an indifference point, respectively. The data distribution was smooth, and a random-effects model performed the best in terms of coefficient significance, monotonicity, and predictive accuracy.

CONCLUSION

Our finding suggests that estimating EQ-5D-Y-3L value sets using cTTO data alone is feasible and therefore could be considered as an option in future valuation studies for EQ-5D-Y-3L.

Discrete Choice Experiments in Health State Valuation: A Systematic Review of Progress and New Trends

BACKGROUND

Discrete choice experiments (DCEs) are increasingly used in health state valuation studies.

OBJECTIVE

This systematic review updates the progress and new findings of DCE studies in the health state valuation, covering the period since the review of June 2018 to November 2022. The review reports the methods that are currently being used in DCE studies to value health and study design characteristics, and, for the first time, reviews DCE health state valuation studies published in the Chinese language.

METHODS

English language databases PubMed and Cochrane, and Chinese language databases Wanfang and CNKI were searched using the self-developed search terms. Health state valuation or methodology study papers were included if the study used DCE data to generate a value set for a preference-based measure. Key information extracted included DCE study design strategies applied, methods for anchoring the latent coefficient on to a 0-1 QALY scale and data analysis methods.

RESULTS

Sixty-five studies were included; one Chinese language publication and 64 English language publications. The number of health state valuation studies using DCE has rapidly increased in recent years and these have been conducted in more countries than prior to 2018. Wide usage of DCE with duration attributes, D-efficient design and models accounting for heterogeneity has continued in recent years. Although more methodological consensus has been found than in studies conducted prior to 2018, this consensus may be driven by valuation studies for common measures with an international protocol (the 'model' valuation research). Valuing long measures with well-being attributes attracted attention and more realistic design strategies (e.g., inconstant time preference, efficient design and implausible states design) were identified. However, more qualitative and quantitative methodology study is still necessary to evaluate the effect of those new methods.

CONCLUSIONS

The use of DCEs in health state valuation continues to grow dramatically and the methodology progress makes the method more reliable and pragmatic. However, study design is driven by international protocols and method selection is not always justified. There is no gold standard for DCE design, presentation format or anchoring method. More qualitative and quantitative methodology study is recommended to evaluate the effect of new methods before researchers make methodology decisions.

Economic burden and health-related quality-of-life among infants with respiratory syncytial virus infection: A multi-country prospective cohort study in Europe

BACKGROUND

Respiratory syncytial virus (RSV) causes a considerable disease burden in young children globally, but reliable estimates of RSV-related costs and health-related quality-of-life (HRQoL) are scarce. This study aimed to evaluate the RSV-associated costs and HRQoL effects in infants and their caregivers in four European countries.

METHODS

Healthy term-born infants were recruited at birth and actively followed up in four European countries. Symptomatic infants were systematically tested for RSV. Caregivers recorded the daily HRQoL of their child and themselves, measured by a modified EQ-5D with Visual Analogue Scale, for 14 consecutive days or until symptoms resolved. At the end of each RSV episode, caregivers reported healthcare resource use and work absenteeism. Direct medical costs per RSV episode were estimated from a healthcare payer's perspective and indirect costs were estimated from a societal perspective. Means and 95% confidence intervals (CI) of direct medical costs, total costs (direct costs + productivity loss) and quality-adjusted life-day (QALD) loss per RSV episode were estimated per RSV episode, as well as per subgroup (medical attendance, country).

RESULTS

Our cohort of 1041 infants experienced 265 RSV episodes with a mean symptom duration of 12.5 days. The mean (95% CI) cost per RSV episode was €399.5 (242.3, 584.2) and €494.3 (317.7, 696.1) from the healthcare payer's and societal perspective, respectively. The mean QALD loss per RSV episode of 1.9 (1.7, 2.1) was independent of medical attendance (in contrast to costs, which also differed by country). Caregiver and infant HRQoL evolved similarly.

CONCLUSION

This study fills essential gaps for future economic evaluations by prospectively estimating direct and indirect costs and HRQoL effects on healthy term infants and caregivers separately, for both medically attended (MA) and non-MA laboratory-confirmed RSV episodes. We generally observed greater HRQoL losses than in previous studies which used non-community and/or non-prospective designs.

Psychometric performance of the Chichewa versions of the EQ-5D-Y-3L and EQ-5D-Y-5L among healthy and sick children and adolescents in Malawi

OBJECTIVES

The EuroQol Group has developed an extended version of the EQ-5D-Y-3L with five response levels for each of its five dimensions (EQ-5D-Y-5L). The psychometric performance has been reported in several studies for the EQ-5D-Y-3L but not for the EQ-5D-Y-5L. This study aimed to psychometrically evaluate the EQ-5D-Y-3L and EQ-5D-Y-5L Chichewa (Malawi) versions.

METHODS

The EQ-5D-Y-3L, EQ-5D-Y-5L and PedsQL™ 4.0 Chichewa versions were administered to children and adolescents aged 8-17 years in Blantyre, Malawi. Both of the EQ-5D-Y versions were evaluated for missing data, floor/ceiling effects, and validity (convergent, discriminant, known-group and empirical).

RESULTS

A total of 289 participants (95 healthy, and 194 chronic and acute) self-completed the questionnaires. There was little problem with missing data (< 5%) except in children aged 8-12 years particularly for the EQ-5D-Y-5L. Ceiling effects was generally reduced in moving from the EQ-5D-Y-3L to the EQ-5D-Y-5L. For both EQ-5D-Y-3L and EQ-5D-Y-5L, convergent validity tested with PedsQL™ 4.0 was found to be satisfactory (correlation ≥ 0.4) at scale level but mixed at dimension /sub-scale level. There was evidence of discriminant validity (p > 0.05) with respect to gender and age, but not for school grade (p < 0.05). For empirical validity, the EQ-5D-Y-5L was 31-91% less efficient than the EQ-5D-Y-3L at detecting differences in health status using external measures.

CONCLUSIONS

Both versions of the EQ-5D-Y-3L and EQ-5D-Y-5L had issues with missing data in younger children. Convergent validity, discriminant validity with respect to gender and age, and known-group validity of either measures were also met for use among children and adolescents in this population, although with some limitations (discriminant validity by grade and empirical validity). The EQ-5D-Y-3L seems particularly suited for use in younger children (8-12 years) and the EQ-5D-Y-5L in adolescents (13-17 years). However, further psychometric testing is required for test re-test reliability and responsiveness that could not be carried out in this study due to COVID-19 restrictions.

Cross-Cultural Adaptation and Validation of the EuroQoL Toddler and Infant Populations Instrument Into Afrikaans for South Africa

OBJECTIVES

The EuroQol Group is exploring the development of a health-related quality of life measure for toddlers and infant populations (EuroQoL Toddler and Infant Populations [EQ-TIPS]) aged 0 to 36 months. This study aimed to report on the cross-cultural adaptation and validity of the South African Afrikaans EQ-TIPS.

METHODS

The development of the Afrikaans EQ-TIPS followed the EuroQol guidelines including forward-backward translation and cognitive interviews with 10 caregivers of children aged 0 to 36 months. Thereafter, 162 caregivers of children 0 to 36 months of age were recruited from a pediatric hospital inpatient and outpatient facility. The EQ-TIPS; Ages and Stages Questionnaire; face, legs, activity, cry, and consolability; and dietary information were completed by all caregivers. The distribution of dimension scores, Spearman's correlation, analysis of variance, and regression analysis were used to explore the validity of the EQ-TIPS.

RESULTS

The descriptive system of the EQ-TIPS was generally well understood and accepted by caregivers. The correlation coefficients for concurrent validity were significant and moderate for pain and weak and significant for the other dimensions hypothesized to correlate. Known groups were compared and inpatients had a significantly higher report of pain (χ² = 7.47, P = .024) and more problems reported across all EQ-TIPS dimensions (recorded on the level sum score) (Kruskal Wallis H = 3.809, P = .05) and reported significantly worse health on the visual analog scale (Kruskal Wallis H = 15.387, P < .001). There were no age-related differences except for a lower report of problems with movement in the 0- to 12-month group (χ² = 10.57, P = .032).

CONCLUSION

The Afrikaans version of the EQ-TIPS is well understood and accepted by caregivers and valid for use with children aged 0 to 36 months in South Africa.

The validity and reliability of the interviewer-administered EQ-5D-Y-3L version in young children

OBJECTIVES

The aim of this study was to determine the validity and reliability of the EQ-5D-Y-3L interviewer-administered (IA) version in South African children aged 5-7-years compared to 8-10-years.

METHODS

Children aged 5-10-years (n = 388) were recruited from healthcare facilities, schools for learners with special educational needs and mainstream schools across four known condition groups: chronic respiratory illnesses, functional disabilities, orthopaedic conditions and the general population. All children completed the EQ-5D-Y-3L IA, Moods and Feelings Questionnaire (MFQ), Faces Pain Scale-Revised (FPS-R) and a functional independence measure (WeeFIM) was completed by the researcher. Cognitive debriefing was done after the EQ-5D-Y-3L IA to determine comprehensibility. Test-retest of the EQ-5D-Y-3L IA was done 48 h later and assessed using Cohen's kappa (k).

RESULTS

Results from children aged 5-7-years (n = 177) and 8-10-years (n = 211) were included. There were significantly higher reports of problems in the Looking After Myself dimension in the 5-7-year-olds (55%) compared to the 8-10-year-olds (28%) (x² = 31.021; p = 0.000). The younger children took significantly longer to complete the measure (Mann-Whitney U = 8389.5, p < 0.001). Known-group validity was found at dimension level with children receiving orthopaedic management reporting more problems on physical dimensions across both age-groups. Convergent validity between Looking After Myself and WeeFIM items of self-care showed moderate to high correlations for both age-groups with a significantly higher correlation in the 8-10-year-olds for dressing upper (z = 2.24; p = 0.013) and lower body (z = 2.78; p = 0.003) and self-care total (z = 2.01; p = 0.022). There were fair to moderate levels of test-retest reliability across age-groups.

CONCLUSION

The EQ-5D-Y-3L IA showed acceptable convergent validity and test-retest reliability for measuring health in children aged 5-7-years. There was more report of problems with the dimension of Looking After Myself in the 5-7-year group due to younger children requiring help with dressing, including buttons and shoelaces due to their developmental age, rather than their physical capabilities. Therefore, it may be useful to include examples of age-appropriate dressing tasks. There was further some reported difficulty with thinking about the dimensions in the younger age-group, most notably for Usual Activities which includes a large number of examples. By decreasing the number of examples it may reduce the burden of recall for the younger age-group.

Preference heterogeneity in health valuation: a latent class analysis of the Peru EQ-5D-5L values

BACKGROUND

Preference heterogeneity in health valuation has become a topic of greater discussion among health technology assessment agencies. To better understand heterogeneity within a national population, valuation studies may identify latent groups that place different absolute and relative importance (i.e., scale and taste parameters) on the attributes of health profiles.

OBJECTIVE

Using discrete choice responses from a Peruvian valuation study, we estimated EQ-5D-5L values on a quality-adjusted life-year (QALY) scale accounting for latent heterogeneity in scale and taste, as well as controlling heteroskedasticity at task level variation.

METHOD

We conducted a series of latent class analyses, each including the 20 main effects of the EQ-5D-5L and a power function that relaxes the constant proportionality assumption (i.e., discounting) between value and lifespan. Taste class membership was conditional on respondent-specific characteristics and their experience with the composite time trade-off (cTTO) tasks. Scale class membership was conditional on behavioral characteristics such as survey duration and self-stated difficulty level in understanding tasks. Each analysis allowed the scale factor to vary by task type and completion time (i.e., heteroskedasticity).

RESULTS

The results indicated three taste classes: a quality-of-life oriented class (33.35%) that placed the highest value on levels of severity, a length-of-life oriented class (26.72%) that placed the highest value on lifespan, and a middle class (39.71%) with health attribute effects lower than the quality class and lifespan effect lower than the length-of-life oriented class. The EQ-5D-5L values ranged from - 2.11 to 0.86 (quality-of-life oriented class), from - 0.38 to 1.02 (middle class), and from 0.36 to 1.01 (length-of-life oriented class). The likelihood of being a member of the quality-of-life class was highly dependent on whether the respondent completed the cTTO tasks (p-value < 0.001), which indicated that the cTTO tasks might cause the Peru respondents to inflate the burden of health problems on a QALY scale compared to those who did not complete the cTTO tasks. The results also showed two scale classes as well as heteroskedasticity within each scale class.

CONCLUSION

Accounting for taste and scale classes simultaneously improveds understanding of preference heterogeneity in health valuation. Future studies may confirm the differences in taste between classes in terms of the effect of quality of life and lifespan attributes. Furthermore, confirmatory evidence is needed on how behavioral variables captured within a study protocol may enhance analyses of preference heterogeneity.

Estimating an EQ-5D-Y-3L Value Set for Indonesia by Mapping the DCE onto TTO Values

BACKGROUND AND OBJECTIVES

Methods for estimating health values in adult populations are well developed, but lag behind in children. The EuroQol standard protocol to arrive at value sets for the youth version of the EQ-5D-Y-3L combines discrete choice experiments with ten composite time trade-off values. Whether ten composite time trade-off values are sufficient remains to be seen and this is one of the reasons the protocol allows for experimental expansion. In this study, 23 health states were administered for the composite time trade-off. This methodological research is embedded in a study aimed at generating a representative value set for EQ-5D-Y-3L in Indonesia.

METHODS

A representative sample of 1072 Indonesian adults each completed 15 discrete choice experiment choice pairs via face-to-face interviews. The discrete choice experiment responses were analysed using a mixed-logit model. To anchor the discrete choice experiment values onto the full health-dead quality-adjusted life-year scale, composite time trade-off values were separately obtained from 222 adults living in Java for 23 EQ-5D-Y-3L states. The derived latent discrete choice experiment values were mapped onto the mean observed composite time trade-off values to create a value set for the EQ-5D-Y-3L. Linear and non-linear mapping models were explored to estimate the most efficient and valid model for the value set.

RESULTS

Coefficients obtained from the choice model were consistent with the monotonic structure of the EQ-5D-Y-3L instrument. The composite time trade-off data showed non-linearity, as the values for the two worst states being evaluated were much lower than predicted by a standard linear model estimated over all composite time trade-off data. Thus, the non-linear mapping strategies with a power term outperformed the linear mapping in terms of mean absolute error. The final model gave a value range from 1.000 for full health (11111) to - 0.086 for the worst health state (33333). Values were most affected by pain/discomfort and least by self-care.

CONCLUSIONS

This article presents the first EQ-5D-Y-3L value set for Indonesia based on the stated preferences of adults asked to consider their views about a 10-year-old child. Mapping the mixed-logit discrete choice experiment model with the inclusion of a power term (without a constant) allowed us to generate a consistent value set for Indonesian youth. Our findings support the expansion of the composite time trade-off part of the EQ-5D-Y valuation study design and show that it would be wise to account for possible non-linearities in updates of the design.

An EQ-5D-Y-3L Value Set for Belgium

BACKGROUND

In Belgium, a value set for children and adolescents for a generic health-related quality-of-life measure is not available. To inform drug pricing and make resource allocation decisions for children and adolescents, national tax-payers' preferences for youth health states should be known.

OBJECTIVE

We aimed to obtain a value set for EQ-5D-Y-3L in Belgium, following the international youth valuation protocol for data collection.

METHODS

Composite Time Trade-Off interviews were conducted in a sample of 200 adults, either face to face or via video conferencing. Another sample of 1000 adults completed an online discrete choice experiment survey. All adults were asked to take the perspective of a 10-year-old child for both methods. Both samples were representative for Belgium in terms of age, sex and region. A latent class analysis was selected to obtain the relative importance of the five dimensions and their levels based on the discrete choice experiment data, which were anchored with the composite Time Trade-Off censored value for the worst health state (33333).

RESULTS

Preferences from Belgian adults revealed a mean censored value for 33333 for children and adolescents of - 0.475. All the estimated coefficients of the model with 4 latent classes were statistically significant and showed higher disutility as severity levels increase. The most important health dimension was pain/discomfort, followed by feeling sad/worried/unhappy.

CONCLUSIONS

This study presents the Belgian EQ-5D-Y-3L value set, which will be included in the Belgian pharmacoeconomic guidelines. The value set enables the calculation of quality-adjusted life-years in children and adolescents, allowing a cost-effectiveness evaluation of health technologies and their youth-specific price setting.

Conceptual Framework for Optimised Proxy Value Set Selection Through Supra-National Value Set Development for the EQ-5D Instruments

BACKGROUND

Preference differences between countries and populations justify the use of country-specific value sets for the EQ-5D instruments. There are no clear criteria based on which the selection of value sets for countries without a national value set should be made. As part of the European PECUNIA project, this study aimed to identify factors contributing to differences in preference-based valuations and develop supra-national value sets for homogenous country clusters in Europe.

METHODS

A literature review was conducted to identify factors relevant to variations in the EQ-5D-3L/5L health state valuations across countries. Factors fulfilling the pre-specified criteria of validity, reliability, international feasibility and comparability were used to group 27 European Union member states, the European Free Trade Association countries and the UK. Clusters of countries were developed based on the frequency of their appearance in the same grouping. The supra-national value sets were estimated for these clusters from the coefficients of existing published valuation studies using the ordinary least-squares model.

RESULTS

Ten factors were identified from 69 studies. From these, five grouping variables: (1) culture and religion; (2) linguistics; (3) healthcare system typology; (4) healthcare system financing; and (5) sociodemographic aspects were derived to define the groups of homogenous countries. Frequency-based grouping revealed five cohesive clusters: English-speaking, Nordic, Central-Western, Southern and Eastern European.

CONCLUSIONS

European countries were clustered considering variables that may relate to differences in health state valuations. Supra-national value sets provide optimised proxy value set selection in the lack of a national value set and/or for regional decision making.

A Value Set for the EQ-5D-Y-3L in the Netherlands

BACKGROUND AND OBJECTIVE

There is increasing interest in preference-accompanied measures of health for paediatric populations. The child-friendly EQ-5D version, EQ-5D-Y-3L, is one such instrument, but the lack of a Dutch value set prevents its use in economic evaluations of healthcare interventions in the Netherlands. This study aims at covering this gap by collecting preferences using a standardised protocol for deriving EQ-5D-Y-3L value sets.

METHODS

Composite time trade-off data were collected using videoconferencing interviews, with each respondent completing ten composite time trade-off tasks. Discrete choice experiment data were collected using an online survey, with respondents each completing 15 paired comparisons. Respondents completed these tasks considering what they prefer for a hypothetical 10-year-old child. Discrete choice experiment data were analysed using a ten-parameter mixed-logit model and anchored to the quality-adjusted life-year scale using the mean observed composite time trade-off values.

RESULTS

The study collected preferences for 197 respondents using composite time trade-off and for 959 respondents using a discrete choice experiment. The discrete choice experiment sample was representative for the Dutch population in terms of age and sex. The level 3 weight for pain/discomfort was the largest, followed by feeling worried, sad or unhappy, usual activities, mobility and self-care. Health state values ranged between -0.218 and 1.

CONCLUSIONS

This study generated a Dutch value set for the EQ-5D-Y-3L, which can be used for the computation of quality-adjusted life-years for economic evaluations of healthcare interventions in paediatric populations.

In a Child's Shoes: Composite Time Trade-Off Valuations for EQ-5D-Y-3L with Different Proxy Perspectives

BACKGROUND AND OBJECTIVES

EQ-5D-Y-3L health states are commonly valued by asking adults to complete stated preference tasks, 'given their views about a 10-year-old child' (hereafter referred to as proxy 1). The use of this perspective has been a source of debate. In this paper, we investigated an alternative proxy perspective: i.e. adults considered what they think a 10-year old-child would decide for itself (hereafter, proxy 2 (substitute)]. Our main objective was to explore how the outcomes, dispersion and response patterns of a composite time trade-off valuation differ between proxy 1 and proxy 2.

METHODS

A team of four trained interviewers completed 402 composite time trade-off interviews following the EQ-5D-Y-3L protocol. Respondents were randomly allocated to value health states in either the proxy 1 or proxy 2 (substitute) perspective. Each respondent valued ten health states with the perspective they were assigned to, as well as one health state with the alternative perspective (33333).

RESULTS

The use of different proxy perspectives yielded differences in EQ-5D-Y-3L valuation. For states in which children had considerable pain and were very worried, sad or unhappy, respondents' valuations were lower in proxy 1 than in proxy 2 (substitute) perspectives, by about 0.2. Within-subject variation across health states was lower for proxy 2 (substitute) than proxy 1 perspectives. Analyses of response patterns suggest that data for proxy 2 (substitute) perspectives were less clustered.

CONCLUSIONS

There are systematic differences between composite time trade-off responses given by adults deciding for children and adults considering what children would want for themselves. In addition to warranting further qualitative exploration, such differences contribute to the ongoing normative discussion surrounding the source and perspective used for valuation of child and adolescent health.

Value Set for the EQ-5D-Y-3L in Hungary

BACKGROUND

The Hungarian health technology assessment guidelines recommend the use of the EuroQol instrument family in quality-adjusted life-year calculations. However, no national value set exists for the EQ-5D-Y-3L or any other youth-specific instrument.

OBJECTIVE

This study aims to develop a national value set of the EQ-5D-Y-3L for Hungary based on preferences of the general adult population.

METHODS

This study followed the international valuation protocol for the EQ-5D-Y-3L. Two independent samples, representative of the Hungarian general adult population in terms of age and sex were recruited to complete online discrete choice experiment (DCE) tasks and composite time trade-off (cTTO) tasks by computer-assisted personal interviews. Adults valued hypothetical EQ-5D-Y-3L health states considering the health of a 10-year-old child. DCE data were modelled using a mixed logit model with random-correlated coefficients. Latent DCE utility estimates were mapped onto mean observed cTTO utilities using ordinary least squares regression.

RESULTS

Overall, 996 and 200 respondents completed the DCE and cTTO surveys, respectively. For each domain, the value set resulted in larger utility decrements with more severe response levels. The relative importance of domains by level 3 coefficients was as follows: having pain or discomfort > feeling worried, sad or unhappy > mobility > doing usual activities > looking after myself. Overall, 12.3% of all health states had negative utilities in the value set, with the worst health state having the lowest predicted utility of - 0.485.

CONCLUSION

This study developed a national value set of the EQ-5D-Y-3L for Hungary. The value set enables to evaluate the cost utility of health technologies for children and adolescents based on societal preferences in Hungary.

Analytical Considerations When Anchoring Discrete Choice Experiment Values Using Composite Time Trade-Off Data: The Case of EQ-5D-Y-3L

Discrete choice experiments (DCEs) are becoming increasingly used to elicit preferences for children's health states. However, DCE data need to be anchored to produce value sets, and composite time trade-off (cTTO) data are typically used in the context of EQ-5D-Y-3L valuation. The objective of this paper is to compare different anchoring methods, summarise the characteristics of the value sets they produce, and outline key considerations for analysts. Three anchoring methods were compared using data from published studies: (1) rescaling using the mean value for the worst health state; (2) linear mapping; and (3) hybrid modelling. The worst state rescaling value set had the largest range. The worst state rescaling and linear mapping value sets preserved the relative importance of the dimensions from the DCE, whereas the hybrid model value set did not. Overall, the predicted values from the hybrid model value set were more closely aligned with the cTTO values. These findings are relatively generalisable. Deciding upon which anchoring approach to use is challenging, as there are numerous considerations. Where cTTO data are collected for more than one health state, anchoring on the worst health state will arguably be suboptimal. However, the final choice of approach may require value judgements to be made. Researchers should seek input from relevant stakeholders when commencing valuation studies to help guide decisions and should clearly set out their rationale for their preferred anchoring approach in study outputs.

Findings from a Roundtable Discussion with US Stakeholders on Valuation of the EQ-5D-Y-3L

OBJECTIVES

The International Valuation Protocol for the valuation of the EQ-5D-Y-3L provides baseline guidance, but country-specific context is also important. This study aimed to obtain US stakeholders' input on key considerations for youth valuation in the US.

METHODS

A total of 14 stakeholders representing various backgrounds were identified via the investigators' networks. A 2-h online meeting was held to discuss (1) the need for a US value set for the EQ-5D-Y-3L; (2) willingness to pay more for quality-adjusted life-year (QALY) gains for children versus adults; (3) sampling strategies; (4) framing perspectives; and (5) other challenges. The session was recorded, transcribed, and summarized.

RESULTS

Several stakeholders supported paying more for QALY gains for children in recognition of their potential future contributions to society, as well as to avoid potential undervaluation and promote access to innovative treatments. Concerns regarding possible double counting, lack of data to showcase long-term benefits, and dangers of paying more for certain subgroups were also expressed. Most of the stakeholders felt that adolescents could relate to a 10-year-old's perspective better than adults and were capable of self-completing valuation tasks, and thus should be directly included in the valuation study. There were concerns that adults would be inconsistent in their views about a 10-year-old, partly depending on their status as a parent.

CONCLUSIONS

US stakeholders provided insights relevant to youth valuation in a US context and were open to continued dialogue with investigators. This study could be useful to investigators who are conducting youth valuation studies in different countries and seeking stakeholder input.

The performance of the EQ-5D-Y-5L compared to the EQ-5D-Y-3L in children and adolescents with cerebral palsy (CP)

Objectives

The aim of this study is to compare the performance and validity of the EQ-5D-Y-3L (Y-3L) and EQ-5D-Y-5L (Y-5L) in South African children and adolescents with cerebral palsy (CP).

Methods

Children/adolescents with CP and those from the general population completed the Y-5L, Y-3L, and PedsQL. Physiotherapists at the school classified participants' functional ability on the Gross Motor Functioning Classification System (GMFCS).

Results

Fifty-one children/adolescents completed the measures. The ceiling effect had a 44% relative reduction for Mobility and floor effects decreased across all dimensions except for Looking After Myself when moving from the Y-3L to Y-5L. Informativity of dimensions improved on average by 0.27 on the Y-5L with similar evenness. There was a range of 6-16% inconsistent responses when moving from the Y-3L to the Y-5L. Convergent validity was strong on paired Y-3L and Y-5L dimensions: Kendall's Tau B (range 0.53 - 0.85) and Gamma (range 0.79 - 0.99). There was significant moderate association between Y-3L and Y-5L with similar items on the PedsQL. The physical dimensions of Mobility, Looking After Myself and Usual Activities were significantly associated with GMFCS with those having less independent mobility reporting more severe problems on dimension scores.

Conclusion

The Y-5L showed a notable reduction in ceiling and floor effects, improved discriminatory power, higher criterion validity with the GMFCS and similar concurrent validity with the PedsQL as the Y-3L. It is recommended that the Y-5L is further tested for reliability and responsiveness in this population group so that its utility for detecting change in clinical trials or as a routine outcome measure can be determined.

EQ-5D-Y Value Set for Germany

BACKGROUND

Demand is increasing for youth-specific preference-based health-related quality-of-life measures for inclusion in evaluations of healthcare interventions for children and adolescents. The EQ-5D-Youth (EQ-5D-Y) has the potential to become such a preference-based measure.

OBJECTIVE

This study applied the recently published EQ-5D-Y valuation protocol to develop a German EQ-5D-Y value set and explored the differences between values given to youth health by parents and non-parents.

METHODS

To elicit EQ-5D-Y health state preferences, a representative sample of 1030 adults of the general population completed a discrete choice experiment (DCE) online survey, and 215 adults participated in face-to-face interviews applying composite time trade-off (cTTO). Respondents were asked to consider a 10-year-old child living in the health states. DCE data were modelled using a mixed logit model. To derive the value set, DCE latent scale values were anchored onto adjusted mean cTTO values using a linear mapping approach.

RESULTS

Adult respondents considered pain/discomfort and feeling worried/sad/unhappy as the two most important dimensions in terms of youth health. Adjusted mean cTTO values ranged from - 0.350 for health state 33333 to 0.970 for health state 21111. The EQ-5D-Y value set showed a logical order for all parameter estimates, and predicted values ranged from - 0.283 to 1. Differences in preferences by parental status were mainly observed for cTTO results, where mean values were larger for parents than for non-parents.

CONCLUSIONS

Applying the valuation protocol, a German EQ-5D-Y value set with internally consistent coefficients was developed. This enables the instrument to be used in economic evaluations of paediatric healthcare interventions.

Estimating an EQ-5D-Y-3L Value Set for China

INTRODUCTION

The standard EQ-5D-Y-3L valuation protocol applies DCE data as the primary preference source to model the relative importance of dimensions while cTTO data served to anchor the DCE coefficients onto the QALY scale. This study aims to estimate an EQ-5D-Y-3L value set for China following this protocol, but with a larger cTTO design to better understand the role of cTTO data in estimating EQ-5D-Y-3L value sets.

METHODS

In total, 150 choice sets and 28 EQ-5D-Y-3L health states were valued using DCE and cTTO methods with two independent samples, respectively. General public from 14 different regions were recruited using quota sampling method to achieve representativeness. We compared two modelling strategies: (1) fit the DCE data with mixed logit model with correlated coefficients and a subsequent mapping procedure for anchoring; (2) fit the DCE and TTO data jointly in a hybrid model. Two evaluation criteria (1) coefficient significance and monotonicity; (2) prediction accuracy of the observed cTTO values were used to select the value set.

RESULTS

In total, 1476 individuals participated in the study, with 1058 participated the DCE interview and 418 participated the cTTO interview. The highest mean TTO value was 0.924 for state 11112 and the lowest mean TTO value was - 0.088 for state 33333. The hybrid model with an A3 term performed the best and was selected as the value set.

DISCUSSION

Following the international protocol and using a larger cTTO design, this study established the EQ-5D-Y-3L value set using a hybrid model for China. Future EQ-5D-Y-3L valuation study could consider using a larger cTTO design for estimating the value set.

Valuing EQ-5D-Y: the current state of play

BACKGROUND

For nearly a decade, value sets for the EQ-5D-Y were not available, reflecting challenges in valuing child HRQoL. A methodological research programme led to publication of a valuation protocol in 2020, which was rapidly taken up by local study teams. By the end of 2022, between 11 and 17 EQ-5D-Y value sets will be available, more than for any other child HRQoL measure. It is timely to review the experience of those using the protocol to identify early learnings and remaining issues where more research is needed.

METHODS

In June 2021, the EuroQol Group organised a three-day workshop, bringing together all those involved in EQ-5D-Y value set studies and related methodological research concerning EQ-5D-Y and valuation. Workshop discussions were captured by note taking and recording all sessions and online chat. A narrative summary of all sessions was produced and synthesised to identify points of agreement and aspects of methods where uncertainty remains.

RESULTS

There was broad agreement that DCE is working well as the principal valuation method. However, the most appropriate means of anchoring the latent scale values produced by DCE remains unclear. Some studies have deviated from the protocol by extending the number of states included in TTO tasks, to better support modelling of DCE and TTO. There is ongoing discussion about the relative merits of alternative variants of TTO and other methods for anchoring. Very few studies have consulted with local end-users to gauge the acceptability of methods used to value EQ-5D-Y.

CONCLUSIONS

Priority areas for research include testing alternative methods for anchoring DCE data; exploring the preferences of adolescents; and scale differences in values for EQ-5D-Y and adult EQ-5D states, and implications of such differences for the use of EQ-5D-Y values in HTA. Given the normative elements of the protocol, engaging with HTA bodies and other local users should be the first step for all future value set studies. Value sets undertaken to date are for the three-level EQ-5D-Y. However, the issues discussed in this paper are equally relevant to valuation of the five-level version of EQ-5D-Y; indeed, similar challenges are encountered valuing any measure of child HRQoL.

Does Changing the Age of a Child to be Considered in 3-Level Version of EQ-5D-Y Discrete Choice Experiment-Based Valuation Studies Affect Health Preferences?

OBJECTIVES

There has been some debate about the choice of perspective and the age of the child considered when completing preference elicitation tasks in the 3-level version of EQ-5D-Y (EQ-5D-Y-3L) valuation protocol. This study aimed to clarify the impact on latent scale EQ-5D-Y-3L values of varying the age of the child experiencing the health state considered by respondents completing the discrete choice experiment (DCE) tasks of the protocol.

METHODS

We conducted an online DCE with a representative sample of 1000 adults in the United Kingdom and 1000 adults in the United States. Respondents selected the health state they prefer from a series of DCE paired EQ-5D-Y-3L health state comparisons using their own perspective and that of a hypothetical child from the following age groups: "5-7 years old," "8-10 years old," "11-13 years old," and "14-15 years old." Data analysis was conducted using separate multinomial logit models for each perspective and country. We also estimated combined models including data from each possible pair of perspectives and used interactions between EQ-5D-Y-3L levels and perspective to determine whether any differences were statistically significant.

RESULTS

No statistically significant differences in coefficients between perspectives were found in the United States. In the United Kingdom, there were differences between the own perspective and the 5 to 7 years old perspective (looking after myself level 3) and between the 5 to 7 years old perspective and the 8 to 10 years old perspective (usual activities level 3).

CONCLUSIONS

Our results suggest that there is minimal impact on latent scale values when using different ages of the hypothetical child in the current EQ-5D-Y-3L valuation protocol.

Measurement properties of the EQ-5D-Y administered through a smartphone app in children with asthma: a longitudinal questionnaire study

BACKGROUND

Asthma impacts children's physical, emotional, and psychosocial Health-Related Quality of Life (HRQL). The EQ-5D-Y is a generic econometric instrument developed to measure HRQL in children.

OBJECTIVE

Evaluation of feasibility, validity, reliability, and responsiveness of EQ-5D-Y descriptive system and utility index to allow the assessment of HRQL in children with asthma, aged 8-11 years (self-response version) or under 8 years old (proxy-response version).

METHODS

We used data from baseline to 10 months of follow-up of an observational, prospective study of children with persistent asthma recruited by pediatricians in Spain (2018-2020). HRQL instruments were administered through a smartphone application: ARCA app. The EQ-5D-Y is composed of a 5-dimension descriptive system, a utility index ranging from 1 to - 0.5392, and a general health visual analogue scale (EQ-VAS). The Pediatric Asthma Impact Scale (PROMIS-PAIS) includes 8 items, providing a raw score. Construct validity hypotheses were stated a priori, and evaluated following two approaches, multitrait-multimethod matrix and known groups' comparisons. Reliability and responsiveness subsamples were defined by stability or change in EQ-VAS and the Asthma Control Questionnaire (ACQ), to estimate the intraclass correlation coefficient (ICC) and the magnitude of change over time.

RESULTS

The EQ-5D-Y was completed at baseline for 119 children (81 self-responded and 38 through proxy response), with a mean age of 9.1 (1.7) years. Mean (SD) of the EQ-5D-Y utility index was 0.93 (0.11), with ceiling and floor effects of 60.3% and 0%, respectively. Multitrait-multimethod matrix confirmed the associations previously hypothesized for the EQ-5D-Y utility index [moderate with PROMIS-PAIS (0.38) and weak with ACQ (0.28)], and for the EQ-5D-Y dimension "problems doing usual activities" [moderate with the ACQ item (0.35) and weak with the PROMIS-PAIS item (0.17)]. Statistically significant differences were found in the EQ-5D-Y between groups defined by asthma control, reliever inhalers use, and second-hand smoke exposure, with mostly moderate effect sizes (0.45-0.75). The ICC of the EQ-5D-Y utility index in the stable subsamples was high (0.81 and 0.79); and responsiveness subsamples presented a moderate to large magnitude of change (0.68 and 0.78), though without statistical significance.

CONCLUSIONS

These results support the use of the EQ-5D-Y as a feasible, valid, and reliable instrument for evaluating HRQL in children with persistent asthma. Further studies are needed on the responsiveness of the EQ-5D-Y in this population.