Indonesia youth population norms for EQ-5D-Y-3 L, EQ-5D-Y-5 L and the PedsQL generic core scale: lower health related quality of life relates to high economic status and stress.

BACKGROUND: The availability of population norms from generic health-related quality of life (HRQoL) instruments can support the interpretation of health outcomes. This study aimed to provide Indonesian youth population norms for the generic HRQoL measures: EQ-5D-Y-3 L, EQ-5D-Y-5 L, and the PedsQL Generic Core Scales. In addition the opportunity arising from the generation of a large representative sample was taken to explore the relationships between HRQoL, health, and socio-economic factors. METHODS: A representative sample of 1103 Indonesian children (aged 8-16 years) completed EQ-5D-Y-3 L, EQ-5D-Y-5 L, the PedsQL Generic Core Scales, and questions related to demographic data and self-reported health status. A stratified quota sampling design was used to represent Indonesian children in terms of residence, age, gender, and geographical area. Family expenses per capita per month were retrieved from parents to determine a child's economic status. RESULTS: The total sample was representative of the Indonesian youth general population. The proportions of participants who reported problems were 43.35% (EQ-5D-Y-3 L), 44.10% (EQ-5D-Y-5 L), and 94.93% (PedsQL Generic), with 31.7% of children reporting health complaints. Older children (13-16 years) reported more problems than younger children (8-12 years). Children living in urban areas reported more problems than children living in rural areas. The lowest value health state reported was '12332' (valued at 0.54), and the minimum EQ VAS score was 60.00. Moderate correlations were found between EQ-5D-Y-3 L values to EQ VAS scores and to PedsQL Total Score. Hierarchical regression analysis showed that females, older age, and having health complaints contributed to a lower level of HRQoL as measured by EQ-5D-Y-3 L values, EQ VAS, and PedsQL Total Score. Remarkably, children with high economic status had lower EQ VAS and PedsQL Total Scores. Among symptoms, 'having stress' had the largest influence with respect to lower EQ-5D-Y-3L values, EQ VAS, and PedsQL Total Score. CONCLUSIONS: Population norms for children's HRQoL as measured by EQ-5D-Y-3 L, EQ-5D-Y-5 L, and the PedsQL Generic Scales are now available for Indonesia. Age, gender, economic status, and health complaints were related to children's HRQoL. These results provide a basis for health studies and health policy for the youth population of Indonesia.

EQ-5D-Y-3L and EQ-5D-Y-5L proxy report: psychometric performance and agreement with self-report.

BACKGROUND: Self-report is the standard for measuring people's health-related quality of life (HRQoL), including children. However, in certain circumstances children cannot report their own health. For this reason, children's HRQoL measures often provide both a self-report and a proxy-report form. It is not clear whether the measurement properties will be the same for these two forms. We investigated whether it would be beneficial to extend the classification system of the EQ-5D-Y proxy questionnaire from 3 to 5 response levels. The agreement between self-report and proxy-report was assessed for both EQ-5D-Y measures. METHODS: The study included 286 pediatric patients and their caregivers as proxies. At three consecutive measurements-baseline, test-retest and follow-up-the proxies assessed the child's HRQoL using the EQ-5D-Y-3L, EQ-5D-Y-5L, the PedsQL Generic, and matched disease-specific instruments. The proxy versions of EQ-5D-Y-3L and EQ-5D-Y-5L were compared in terms of feasibility, distribution properties, convergent validity, test-retest and responsiveness. Agreement between both EQ-5D-Y proxy versions to their respective self-report versions was assessed at baseline and follow-up. RESULTS: The proportion of missing responses was 1% for the EQ-5D-Y-3L and 1.4% for the EQ-5D-Y-5L. The frequency of health state with no problems in all dimensions (11111) was slightly lower for the EQ-5D-Y-5L (21.3% vs 16.7%). Regarding the convergent validity with the PedsQL and disease-specific measures, the proxy versions of EQ-5D-Y-3L and EQ-5D-Y-5L had similar magnitudes of associations between similar dimensions. The means of test-retest coefficients between the two versions of the EQ-5D-Y proxy were comparable (0.83 vs. 0.84). Regarding reported improved conditions, responsiveness of the EQ-5D-Y-5L proxy (26.6-54.1%) was higher than that of the EQ-5D-Y-3L proxy (20.7-46.4%). Except for acutely ill patients, agreement between the EQ-5D-Y-5L proxy and self-reports was at least moderate. CONCLUSIONS: Extending the number of levels of the proxy version of EQ-5D-Y can improve the classification accuracy and the ability to detect health changes over time. The level structure of EQ-5D-Y-5L was associated with a closer agreement between proxy and self-report. The study findings support extending the EQ-5D-Y descriptive system from 3 to 5 levels when administered by a proxy, which is often the case in the pediatric population.

Comparing measurement properties of EQ-5D-Y-3L and EQ-5D-Y-5L in paediatric patients.

BACKGROUND: The adult versions EQ-5D-3L and EQ-5D-5L have been extensive compared. This is not the case for the EQ-5D youth versions. The study aim was to compare the measurement properties and responsiveness of EQ-5D-Y-3L and EQ-5D-Y-5L in paediatric patients. METHODS: A sample of patients 8-16 years old with different diseases and a wide range of disease severity was asked to complete EQ-5D-Y-3L, EQ-5D-Y-5L, PedsQL Generic Core Scale, and selected, appropriate disease-specific instruments, three times. EQ-5D-Y-3L and EQ-5D-Y-5L were compared in terms of: feasibility, (re-)distribution properties, discriminatory power, convergent validity, test-retest reliability, and responsiveness. RESULTS: 286 participating patients suffered from one of the following diseases: major beta-thalassemia, haemophilia, acute lymphoblastic leukaemia, acute illness. Missing responses were comparable between versions of the EQ-5D-Y, suggesting comparable feasibility. The number of patients in the best health state (level profile 11111) was equal in both EQ-5D-Y versions. The projection of EQ-5D-Y-3L scores onto EQ-5D-Y-5L for all dimensions showed that the two additional levels in EQ-5D-Y-5L slightly improved the accuracy of patients in reporting their problems, especially if severe. Convergent validity with PedsQL and disease-specific measures showed that the two EQ-5D-Y versions performed about equally. Test-retest reliability (EQ-5D-Y-3L 0.78 vs EQ-5D-Y-5L 0.84), and sensitivity for detecting health changes, were both better in EQ-5D-Y-5L. CONCLUSIONS: Extending the number of levels did not give clear superiority to EQ-5D-Y-5L over EQ-5D-Y-3L based on the criteria assessed in this study. However, increasing the number of levels benefitted EQ-5D-Y performance in the measurement of moderate to severe problems and especially in longitudinal study designs.

Test-Retest Reliability of EQ-5D-5L Valuation Techniques: The Composite Time Trade-Off and Discrete Choice Experiments.

OBJECTIVES: To explore the test-retest reliability of the composite time trade-off (C-TTO) and discrete choice experiment (DCE) used in the Indonesian five-level EuroQol five-dimensional questionnaire (EQ-5D-5L) valuation study. METHODS: A representative sample aged 17 years and older was recruited from the Indonesian general population by stratified quota sampling with respect to residence, sex, and age. Trained interviewers conducted computer-assisted face-to-face interviews using the EuroQol valuation technology. Each respondent valued 10 health states using C-TTO and 7 pairs of health states in a DCE exercise. The retest interview was conducted after 2 weeks by the same interviewer. The Wilcoxon matched-pairs signed-rank test, intraclass correlation coefficient, and multilevel regression were applied in comparing the C-TTO test and retest data. For DCE, the analysis of proportions was used. RESULTS: A total of 226 respondents with characteristics similar to the Indonesian population completed the retest interview. For C-TTO, 82 (95.3%) of 86 health states had no significant mean value differences between test and retest. The mean value of the second test was statistically significantly higher than that of the first test by 0.042. For DCE, 72.5% of responses were identical. DCE retest showed a different pattern concerning the relative importance of the dimensions, whereas the C-TTO remained the same. CONCLUSIONS: C-TTO is stable over time, whereas in DCE the relative values of the dimensions shift. The results support the use of the C-TTO, in particular the Indonesian EQ-5D-5L value set, and suggest a critical examination of the reliability of DCE results over time.

Living in uncertainty due to floods and pollution: the health status and quality of life of people living on an unhealthy riverbank.

BACKGROUND: People living on the banks of polluted rivers with yearly flooding lived in impoverished and physically unhealthy circumstances. However, they were reluctant to move or be relocated to other locations where better living conditions were available. This study aimed to investigate the health status, quality of life (QoL), happiness, and life satisfaction of the people who were living on the banks of one of the main rivers in Jakarta, Indonesia, the Ciliwung. METHODS: Respondents were 17 years and older and recruited from the Bukit Duri community (n = 204). Three comparison samples comprised: i) a socio-demographically matched control group, not living on the river bank (n = 204); ii) inhabitants of Jakarta (n = 305), and iii) the Indonesian general population (n = 1041). Health status and QoL were measured utilizing EQ-5D-5L, WHOQOL-BREF, the Happiness Scale, and the Life Satisfaction Index. A visual analogue scale question concerning respondents' financial situations was added. MANOVA and multivariate regression analysis were used to analyze the differences between the Ciliwung respondents and the three comparison groups. RESULTS: The Ciliwung respondents reported lower physical QoL on WHOQOL-BREF and less personal happiness than the matched controls but rated their health (EQ-5D-5L) and life satisfaction better than the matched controls. Similar results were obtained by comparison with the Jakarta inhabitants and the general population. Bukit Duri inhabitants also perceived themselves as being in a better financial situation than the three comparison groups even though their incomes were lower. CONCLUSIONS: The recent relocation to a better environment with better housing might improve the former Ciliwung inhabitants' quality of life and happiness, but not necessarily their perceived health, satisfaction with life, and financial situations.

Employing quality control and feedback to the EQ-5D-5L valuation protocol to improve the quality of data collection.

OBJECTIVES: In valuing health states using generic questionnaires such as EQ-5D, there are unrevealed issues with the quality of the data collection. The aims were to describe the problems encountered during valuation and to evaluate a quality control report and subsequent retraining of interviewers in improving this valuation. METHODS: Data from the first 266 respondents in an EQ-5D-5L valuation study were used. Interviewers were trained and answered questions regarding problems during these initial interviews. Thematic analysis was used, and individual feedback was provided. After completion of 98 interviews, a first quantitative quality control (QC) report was generated, followed by a 1-day retraining program. Subsequently individual feedback was also given on the basis of follow-up QCs. The Wilcoxon signed-rank test was used to assess improvements based on 7 indicators of quality as identified in the first QC and the QC conducted after a further 168 interviews. RESULTS: Interviewers encountered problems in recruiting respondents. Solutions provided were: optimization of the time of interview, the use of broader networks and the use of different scripts to explain the project's goals to respondents. For problems in interviewing process, solutions applied were: developing the technical and personal skills of the interviewers and stimulating the respondents' thought processes. There were also technical problems related to hardware, software and internet connections. There was an improvement in all 7 indicators of quality after the second QC. CONCLUSION: Training before and during a study, and individual feedback on the basis of a quantitative QC, can increase the validity of values obtained from generic questionnaires.

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.

Quality of life of the Indonesian general population: Test-retest reliability and population norms of the EQ-5D-5L and WHOQOL-BREF.

OBJECTIVES: The objective of this study is to obtain population norms and to assess test-retest reliability of EQ-5D-5L and WHOQOL-BREF for the Indonesian population. METHODS: A representative sample of 1056 people aged 17-75 years was recruited from the Indonesian general population. We used a multistage stratified quota sampling method with respect to residence, gender, age, education level, religion and ethnicity. Respondents completed EQ-5D-5L and WHOQOL-BREF with help from an interviewer. Norms data for both instruments were reported. For the test-retest evaluations, a sub-sample of 206 respondents completed both instruments twice. RESULTS: The total sample and test-retest sub-sample were representative of the Indonesian general population. The EQ-5D-5L shows almost perfect agreement between the two tests (Gwet's AC: 0.85-0.99 and percentage agreement: 90-99%) regarding the five dimensions. However, the agreement of EQ-VAS and index scores can be considered as poor (ICC: 0.45 and 0.37 respectively). For the WHOQOL-BREF, ICCs of the four domains were between 0.70 and 0.79, which indicates moderate to good agreement. For EQ-5D-5L, it was shown that female and older respondents had lower EQ-index scores, whilst rural, younger and higher-educated respondents had higher EQ-VAS scores. For WHOQOL-BREF: male, younger, higher-educated, high-income respondents had the highest scores in most of the domains, overall quality of life, and health satisfaction. CONCLUSIONS: This study provides representative estimates of self-reported health status and quality of life for the general Indonesian population as assessed by the EQ-5D-5L and WHOQOL-BREF instruments. The descriptive system of the EQ-5D-5L and the WHOQOL-BREF have high test-retest reliability while the EQ-VAS and the index score of EQ-5D-5L show poor agreement between the two tests. Our results can be useful to researchers and clinicians who can compare their findings with respect to these concepts with those of the Indonesian general population.

The Indonesian EQ-5D-5L Value Set.

BACKGROUND: The EQ-5D is one of the most used generic health-related quality-of-life (HRQOL) instruments worldwide. To make the EQ-5D suitable for use in economic evaluations, a societal-based value set is needed. Indonesia does not have such a value set. OBJECTIVE: The aim of this study was to derive an EQ-5D-5L value set from the Indonesian general population. METHODS: A representative sample aged 17 years and over was recruited from the Indonesian general population. A multi-stage stratified quota method with respect to residence, gender, age, level of education, religion and ethnicity was utilized. Two elicitation techniques, the composite time trade-off (C-TTO) and discrete choice experiments (DCE) were applied. Interviews were undertaken by trained interviewers using computer-assisted face-to-face interviews with the EuroQol Valuation Technology (EQ-VT) platform. To estimate the value set, a hybrid regression model combining C-TTO and DCE data was used. RESULTS: A total of 1054 respondents who completed the interview formed the sample for the analysis. Their characteristics were similar to those of the Indonesian population. Most self-reported health problems were observed in the pain/discomfort dimension (39.66%) and least in the self-care dimension (1.89%). In the value set, the maximum value was 1.000 for full health (health state '11111') followed by the health state '11112' with value 0.921. The minimum value was -0.865 for the worst state ('55555'). Preference values were most affected by mobility and least by pain/discomfort. CONCLUSIONS: We now have a representative EQ-5D-5L value set for Indonesia. We expect our results will promote and facilitate health economic evaluations and HRQOL research in Indonesia.