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

Understanding Canadian stakeholders' views on measuring and valuing health for children and adolescents: a qualitative study

OBJECTIVE

Valuing child health is critical to assessing the value of healthcare interventions for children. However, there remain important methodological and normative issues. This qualitative study aimed to understand the views of Canadian stakeholders on these issues.

METHODS

Stakeholders from health technology assessment (HTA) agencies, pharmaceutical industry representatives, healthcare providers, and academic researchers/scholars were invited to attend an online interview. Semi-structured interviews were designed to focus on: (1) comparing the 3-level and 5-level versions of the EQ-5D-Y; (2) source of preferences for valuation (adults vs. children); (3) perspective of valuation tasks; and (4) methods for valuation (discrete choice experiment [DCE] and its variants versus time trade-off [TTO]). Participants were probed to consider HTA guidelines, cognitive capacity, and potential ethical concerns. All interviews were recorded and transcribed verbatim. Framework analysis with the incidence density method was used to analyze the data.

RESULTS

Fifteen interviews were conducted between May and September 2022. 66.7% (N = 10) of participants had experience with economic evaluations, and 86.7% (N = 13) were parents. Eleven participants preferred the EQ-5D-Y-5L. 12 participants suggested that adolescents should be directly involved in child health valuation from their own perspective. The participants were split on the ethical concerns. Eight participants did not think that there was ethical concern. 11 participants preferred DCE to TTO. Among the DCE variants, 6 participants preferred the DCE with duration to the DCE with death.

CONCLUSIONS

Most Canadian stakeholders supported eliciting the preferences of adolescents directly from their own perspective for child health valuation. DCE was preferred if adolescents are directly involved.

The RETRIEVE Checklist for Studies Reporting the Elicitation of Stated Preferences for Child Health-Related Quality of Life

BACKGROUND

Recent systematic reviews show varying methods for eliciting, modelling, and reporting preference-based values for child health-related quality-of-life (HRQoL) outcomes, thus producing value sets with different characteristics. Reporting in many of the reviewed studies was found to be incomplete and inconsistent, making them difficult to assess. Checklists can help to improve standards of reporting; however, existing checklists do not address methodological issues for valuing child HRQoL. Existing checklists also focus on reporting methods and processes used in developing HRQoL values, with less focus on reporting of the values' key characteristics and properties. We aimed to develop a checklist for studies generating values for child HRQoL, including for disease-specific states and value sets for generic child HRQoL instruments.

DEVELOPMENT

A conceptual model provided a structure for grouping items into five modules. Potential items were sourced from an adult HRQoL checklist review, with additional items specific to children developed using recent reviews. Checklist items were reduced by eliminating duplication and overlap, then refined for relevance and clarity via an iterative process. Long and short checklist versions were produced for different user needs. The resulting long RETRIEVE contains 83 items, with modules for reporting methods (A-D) and characteristics of values (E), for researchers planning and reporting child health valuation studies. The short RETRIEVE contains 14 items for decision makers or researchers choosing value sets.

CONCLUSION

Applying the RETRIEVE checklists to relevant studies suggests feasibility. RETRIEVE has the potential to improve completeness in the reporting of preference-based values for child HRQOL outcomes and to improve assessment of preference-based value sets.

Validity and responsiveness of EQ-5D-Y in children with haematological malignancies and their caregivers

The psychometric properties of the EQ-5D-Y have not been widely tested in severely ill children. The aim of this study was to assess and compare the validity and responsiveness of the EQ-5D-Y-3L and EQ-5D-Y-5L in paediatric inpatients with haematological malignancies and caregivers. Respondents completed the interviewer-administered self-complete or proxy version of the EQ-5D-Y-3L and EQ-5D-Y-5L and an overall health assessment twice on different days. Known-groups validity was assessed by comparing patients who differed in overall health and Eastern Cooperative Oncology Group (ECOG) performance. Responsiveness to worsened health was assessed using standardised effect size (SES) for patients with worsened ECOG grade, self-reported rating, or chemotherapy initiation. Ninety-six dyads completed the baseline questionnaires. A smaller proportion of patients reported "no problems" on the EQ-5D-Y-5L compared to EQ-5D-Y-3L for most of the five dimensions. Patients in poor health reported more problems in all dimensions and had higher EQ-5D-Y-5L level sum score, lower EQ VAS and EQ-5D-Y-3L index scores (Cohen's d ES: 0.32-1.38 for patients; 0.50-2.05 for caregivers). There was a mild to good responsiveness to worsened health condition based on ECOG (SES: 0.14-0.61 for patients; 0.40-0.96 for caregivers), suggesting the proxy version was slightly responsive than the self-complete version of both instruments. The results demonstrated validity and responsiveness for both the self-complete and proxy versions of the EQ-5D-Y-3L and EQ-5D-Y-5L. The proxy and 5-level versions of the instrument were more sensitive than the self-complete and 3-level versions in this patient group.

Testing 2 Alternative Time Trade-Off Methods for Valuation of Children's Health States

OBJECTIVES

Composite time trade-off (cTTO) values for EQ-5D-Y-3L health states tend to be high, raising concerns about sensitivity particularly for mild or moderate health states. We conceptualized and pilot tested 2 alternative time trade-off (TTO) variants: the caregiver TTO (CGTTO) and lag-time TTO (LTTO).

METHODS

We collected CGTTO and LTTO data in China for 10 EQ-5D-Y-3L health states and compared the resulting values, respondent feedback, and task completion times with those from an EQ-5D-Y-3L valuation study using cTTO. We also examined how age and parental status of respondents could affect TTO values.

RESULTS

A total of 304 participants were included in this study. Overall, cTTO showed statistically better results in all feedback questions. On a 5-point Likert scale where lower score means greater agreement, the mean (SD) feedback scores for cTTO, LTTO, and CGTTO were 1.18 (0.58), 1.45 (0.91), and 1.65 (1.02) for "easy to understand"; 1.45 (0.91), 1.94 (1.08), and 1.86 (1.24) for "easy to differentiate"; and 3.61 (1.29), 2.97 (1.33), and 3.02 (1.50) for "difficult to decide," respectively. The mean (SD) TTO values of all 10 states were 0.463 (0.494), 0.387 (0.555), and 0.123 (0.710) for cTTO, LTTO, and CGTTO, respectively. The effects of age and parental status on TTO values differed by the 3 methods.

CONCLUSIONS

LTTO and CGTTO produce values with good characteristics and merit further investigation. Researchers need to be aware of the differences in design and values when using the TTO method to value children's health states.

Psychometric Comparison of EQ-5D-Y, CHU-9D, and PedsQL 4.0 in Chinese Children and Adolescents With Functional Dyspepsia: A Multicenter Study

OBJECTIVES

This study aimed to assess and compare psychometric properties of the 3 health-related quality of life (HRQOL) instruments EQ-5D Youth version (EQ-5D-Y), Child Health Utility 9D (CHU-9D), and Pediatric Quality of Life Inventory 4.0 (PedsQL 4.0) in children and adolescents with functional dyspepsia (FD) in China.

METHODS

A consecutive sample of FD outpatients were recruited from 6 tertiary medical centers in Hangzhou. The patients self-completed the 3 instruments in random order. Their feasibility, acceptability, construct validity (convergent, divergent, and known-group validity), and sensitivity were assessed. Multiple linear regression was used for identifying HRQOL-associated factors.

RESULTS

A total of 1100 patients (mean age, 9.2 years; girl, 56.8%) completed the survey with no missing responses. Ceiling effect was quite higher in EQ-5D-Y (60.9%) than CHU-9D (33.8%) and PedsQL 4.0 (1.0%). The EQ-5D-Y and CHU-9D utility scores and PedsQL 4.0 total score were highly correlated (|r| = 0.593-0.661), except for the EuroQol visual analog scale score (EQ-VAS). The intraclass correlation coefficient between the 2 utility scores was fair (0.542). Most conceptually similar dimensions among the 3 instruments showed moderate to high correlations (|r| > 0.3) as hypothesized. The difference was statistically significant for the 2 utility scores and PedsQL 4.0 total score in varied severity groups (P < .001), and PedsQL 4.0 total score had higher relative efficiency and effect size values. The child's age, severity of FD symptoms, and their guardian's education had significant impact on HRQOL (P < .001).

CONCLUSIONS

EQ-5D-Y, CHU-9D, and PedsQL 4.0 demonstrated acceptable psychometric properties in Chinese children with FD. PedsQL 4.0 showed superior sensitivity and is recommended. EQ-5D-Y and CHU-9D utility scores were not interchangeable. The measurement properties of EQ-VAS need to be further explored.

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.

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.

Efficient Designs for Valuation Studies That Use Time Tradeoff (TTO) Tasks to Map Latent Utilities from Discrete Choice Experiments to the Interval Scale: Selection of Health States for TTO Tasks

BACKGROUND

In eliciting utilities to value multiattribute utility instruments, discrete choice experiments (DCEs) administered online are less costly than interviewer-facilitated time tradeoff (TTO) tasks. DCEs capture utilities on a latent scale and are often coupled with a small number of TTO tasks to anchor utilities to the interval scale. Given the costly nature of TTO data, design strategies that maximize value set precision per TTO response are critical.

METHODS

Under simplifying assumptions, we expressed the mean square prediction error (MSE) of the final value set as a function of the number J of TTO-valued health states and the variance VJ of the states' latent utilities. We hypothesized that even when these assumptions do not hold, the MSE 1) decreases as VJ increases while holding J fixed and 2) decreases as J increases while holding VJ fixed. We used simulation to examine whether there was empirical support for our hypotheses a) assuming an underlying linear relationship between TTO and DCE utilities and b) using published results from the Dutch, US, and Indonesian EQ-5D-5L valuation studies.

RESULTS

Simulation set (a) supported the hypotheses, as did simulations parameterized using valuation data from Indonesia, which showed a linear relationship between TTO and DCE utilities. The US and Dutch valuation data showed nonlinear relationships between TTO and DCE utilities and did not support the hypotheses. Specifically, for fixed J, smaller values of VJ reduced rather than increased the MSE.

CONCLUSIONS

Given that, in practice, the underlying relationship between TTO and DCE utilities may be nonlinear, health states for TTO valuation should be placed evenly across the latent utility scale to avoid systematic bias in some regions of the scale.

HIGHLIGHTS

Valuation studies may feature a large number of respondents completing discrete choice tasks online, with a smaller number of respondents completing time tradeoff (TTO) tasks to anchor the discrete choice utilities to an interval scale.We show that having each TTO respondent complete multiple tasks rather than a single task improves value set precision.Keeping the total number of TTO respondents and the number of tasks per respondent fixed, having 20 health states directly valued through TTO leads to better predictive precision than valuing 10 health states directly.If DCE latent utilities and TTO utilities follow a perfect linear relationship, choosing the TTO states to be valued by weighting on the 2 ends of the latent utility scale leads to better predictive precision than choosing states evenly across the latent utility scale.Conversely, if DCE latent utilities and TTO utilities do not follow a linear relationship, choosing the states to be valued using TTO evenly across the latent utility scale leads to better predictive precision than weighted selection does.In the context of valuation of the EQ-5D-Y-3L, we recommend valuing 20 or more health states using TTO and placing them evenly across the latent utility scale.