Assessing Outcomes for Cost-Utility Analysis in Children and Adolescents With Mental Health Problems: Are Multiattribute Utility Instruments Fit for Purpose?

Comparison of the EQ-5D-Y and the CHU-9D instruments in a general child population based on self-reports and proxy-reports

OBJECTIVE

This study utilized the EQ-5D-Y and the Child Health Utility 9D (CHU-9D) instruments to empirically investigate a general child population aged 7-8 years in China, with the aim of assessing and comparing the performance, correlation, and agreement between these two instruments. Both self-reported and proxy-reported versions of the instruments were considered in the analysis.

METHODS

Data were collected from 7-8-year-old students in the second grade from four schools in Guangxi and Guiyang provinces, China. Children and their proxies independently completed their respective versions of the questionnaires, including the EQ-5D-Y, the CHU-9D, and other socio-demographic information. The psychometric properties of the EQ-5D-Y and the CHU-9D were assessed, including ceiling effects, internal consistency, and known-group validity. Spearman's correlation coefficient, Intraclass Correlation Coefficient (ICC), and Bland-Altman plots were calculated and plotted to assess the correlation and agreement between the EQ-5D-Y and CHU-9D.

RESULTS

A total of 369 pairs of valid questionnaires were collected from both children and proxies. Due to the study's focus on a general child population, both EQ-5D-Y and CHU-9D yielded high utility values, with a significant ceiling effect observed, particularly in the EQ-5D-Y proxy-reported results. Compared to the EQ-5D-Y, the CHU-9D demonstrated a higher Cronbach's alpha coefficient and better internal consistency. Both instruments also demonstrated known-group validity, distinguishing different health status groups, except for EQ-5D-Y proxy-reported results. Spearman's correlation coefficient indicated some correlations in similar dimensions and utility values between the EQ-5D-Y and CHU-9D. The ICC of the EQ-5D-Y and CHU-9D utility values was 0.290 for self-reports and 0.383 for proxy-reports, indicating poor agreement between the two instruments. The Bland-Altman plots showed that the mean utility values obtained from EQ-5D-Y were significantly higher than those from CHU-9D.

CONCLUSION

The EQ-5D-Y and the CHU-9D demonstrated acceptable performance within the general child population aged 7-8 years in China, except for the EQ-5D-Y proxy-reported version. It suffered from a notable ceiling effect, poor internal consistency, as well as weak known-group validity and discriminative ability. Moreover, although there existed a certain degree of correlation between the EQ-5D-Y and CHU-9D, their utility values exhibited significant differences. Therefore, these instruments are not interchangeable in practice.

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/ .

How do children understand and respond to the EQ-5D-Y-3L? A mixed methods study in a community-based sample of 6-12-year-olds

BACKGROUND

The EQ-5D-Y-3L is widely used for measuring and valuing HRQoL in paediatric populations. This mixed methods study used the EQ-5D-Y-3L measure and applied a retrospective think-aloud approach to examine the self-report validity in children of varying chronological age.

METHODS

A mixed methods study was conducted in a community-based sample of 39 children aged 6-12 years. In a semi-structured interview, children self-completed the EQ-5D-Y-3L and then engaged in retrospective think-aloud. Conversations were audio-recorded and transcribed for analysis in NVivo using the Tourangeau four-stage response model framework to assess comprehension, judgment, recall, and response mapping issues. Fisher's exact test was used to assess the differences between child-self reported HRQoL across subgroups. The inter-rater agreement between child-parent dyads was assessed with CCC for overall HRQoL and Gwet's AC1 for dimension level HRQoL.

RESULTS

Overall, response issues were detected in n = 18 (46%) children. Comprehension issues were apparent in the "having pain or discomfort" dimension where children found it challenging to understand 'discomfort'. Recall-related issues were observed where children's responses were influenced by their typical tendencies (e.g., being usually worried) or past incidences (e.g., feeling pain sometimes). Judgement-related issues were the most common, particularly in the "doing usual activities" dimension, where children tended to respond based on their self-perceived ability to engage in activities rather than health-related limitations. None of the participants were found to have problems with response mapping. A healthy lifestyle that included diet and exercise was a notable consideration in EQ VAS ratings. The younger age groups had a higher proportion of response issues (6-7 years: 64%, 8-10 years: 62%), compared to older children (11-12 years: 20%). Moreover, children with response issues demonstrated significantly lower EQ-5D-Y-3L scores (mean = 0.78, se = 0.04) as compared to those without (mean = 0.95, se = 0.02) (p-value < 0.001). The overall inter-rater agreement was higher for those without any response issues (CCC = 0.33) than those with (CCC = 0.14). Additionally, higher agreement was noted across all the five dimensions in the subgroup with no response issues relative to those with.

CONCLUSIONS

Children in the general community may have different perceptions of HRQoL when responding to the EQ-5D-Y-3L possibly due to their limited experience with health-related challenges. The retrospective think-aloud approach adopted highlighted the relatively higher prevalence of response issues in the younger children (ages < 11 years), indicating the need for careful interpretation of self-reported HRQoL using the current version of the EQ-5D-Y-3L in this population.

Comparing the Psychometric Performance of Generic Paediatric Health-Related Quality of Life Instruments in Children and Adolescents with ADHD, Anxiety and/or Depression

OBJECTIVE

The aim of this study was to examine the validity, reliability and responsiveness of common generic paediatric health-related quality of life (HRQoL) instruments in children and adolescents with mental health challenges.

METHODS

Participants were a subset of the Australian Paediatric Multi-Instrument Comparison (P-MIC) study and comprised 1013 children aged 4-18 years with attention-deficit/hyperactivity disorder (ADHD) (n = 533), or anxiety and/or depression (n = 480). Participants completed an online survey including a range of generic paediatric HRQoL instruments (PedsQL, EQ-5D-Y-3L, EQ-5D-Y-5L, CHU9D) and mental health symptom measures (SDQ, SWAN, RCADS-25). A subset of participants also completed the HUI3 and AQoL-6D. The psychometric performance of each HRQoL instrument was assessed regarding acceptability/feasibility; floor/ceiling effects; convergent validity; known-group validity; responsiveness and test-retest reliability.

RESULTS

The PedsQL, CHU9D, EQ-5D-Y-3L and EQ-5D-Y-5L showed similarly good performance for acceptability/feasibility, known-group validity and convergent validity. The CHU9D and PedsQL showed no floor or ceiling effects and fair-good test-retest reliability. Test-retest reliability was lower for the EQ-5D-Y-3L and EQ-5D-Y-5L. The EQ-5D-Y-3L showed the highest ceiling effects, but was the top performing instrument alongside the CHU9D on responsiveness to improvements in health status, followed by the PedsQL. The AQoL-6D and HUI3 showed good acceptability/feasibility, no floor or ceiling effects, and good convergent validity, yet poorer performance on known-group validity. Responsiveness and test-retest reliability were not able to be assessed for these two instruments. In subgroup analyses, performance was similar for all instruments for acceptability/feasibility, known-group and convergent validity, however, relative strengths and weaknesses for each instrument were noted for ceiling effects, responsiveness and test-retest reliability. In sensitivity analyses using utility scores, performance regarding known-group and convergent validity worsened slightly for the EQ-5D-Y-3L and CHU9D, though improved slightly for the HUI3 and AQoL-6D.

CONCLUSIONS

While each instrument showed strong performance in some areas, careful consideration of the choice of instrument is advised, as this may differ dependent on the intended use of the instrument, and the age, gender and type of mental health condition of the population in which the instrument is being used.

TRIAL REGISTRATION

ANZCTR-ACTRN12621000657820.