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Valuation of EQ-5D-3L Health States in Singapore: Modeling of Time Trade-Off Values for 80 Empirically Observed Health States

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Abstract

Objective

The aim of this study was to establish an EQ-5D-3L value set using the time trade-off (TTO) method to elicit the health preferences of the general Singaporean population.

Methods

The values of 80 EQ-5D-3L health states were elicited from a general Singaporean population sample using a TTO method. In face-to-face interviews, participants were asked to value a block of ten health states. Various linear regression models were examined to assess for goodness of fit to the data, at both aggregate and individual levels. Prediction precision was assessed in terms of mean absolute error (MAE), and numbers of prediction errors larger than 0.10 and 0.20. Prediction consistency and bias were also assessed.

Results

A total of 456 participants provided data for this study. The N3 model without a constant estimated using the aggregate data exhibited the best fit of the data, predicted values with the least bias, and generated logically consistent values for all 243 EQ-5D-3L health states. The MAE was 0.1137, and 35 of 80 predicted values had errors less than 0.10 in absolute magnitude. Based on this model, the utility values ranged from 0.854 for state 11121 to −0.769 for state 33333.

Conclusions

The EQ-5D-3L value set can be estimated using the TTO method in the multi-cultural, multi-ethnic Singapore. Although the estimation precision is not optimal, the health-state preference values generated in this study are useful to health service researchers in the country before estimates with smaller errors are available.

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References

  1. Torrance GW. Measurement of health state utilities for economic appraisal. J Health Econ. 1986;5:1–30.

    Article  CAS  PubMed  Google Scholar 

  2. Dolan P. Valuing health-related quality of life: issues and controversies. Pharmacoeconomics. 1999;15:119–27.

    Article  CAS  PubMed  Google Scholar 

  3. Torrance GW, Thomas WH, Sackett DL. A utility maximization model for evaluation of health care programs. Health Serv Res. 1972;7:118–33.

    CAS  PubMed Central  PubMed  Google Scholar 

  4. Dolan P. Modeling valuations for EuroQol health states. Med Care. 1997;35:1095–108.

    Article  CAS  PubMed  Google Scholar 

  5. Feeny DH, Furlong WJ, Torrance GW, et al. Multiattribute and single attribute utility functions for the health utilities index mark 3 system. Med Care. 2002;40:113–28.

    Article  PubMed  Google Scholar 

  6. Brazier JE, Roberts J, Deverill MD. The estimation of a preference-based measure of health from the SF-36. J Health Econ. 2002;21:271–92.

    Article  PubMed  Google Scholar 

  7. Shaw JW, Johnson JA, Coons SJ. US valuation of the EQ-5D health states: development and testing of the D1 valuation model. Med Care. 2007;45:238–44.

    Article  Google Scholar 

  8. Lee YK, Nam HS, Chuang LH, et al. South Korean time trade-off values for EQ-5D health states: modeling with observed values for 101 health states. Value Health. 2009;12:1187–93.

    Article  PubMed  Google Scholar 

  9. Tsuchiya A, Ikeda S, Ikegami N, et al. Estimating an EQ-5D population value set: the case of Japan. Health Econ. 2002;11:341–53.

    Article  PubMed  Google Scholar 

  10. Tongsiri S, Cairns J. Estimating population-based values for EQ-5D health states in Thailand. Value Health. 2011;14:1142–5.

    Article  PubMed  Google Scholar 

  11. Yusof FA, Goh A, Azmi S. Estimating an EQ-5D value set for Malaysia using time trade-off and visual analogue scale methods. Value Health. 2012;15:S85–90.

    Article  PubMed  Google Scholar 

  12. Golicki D, Jakubczyk M, Niewada M, et al. Valuation of EQ-5D health states in Poland: first TTO-based social value set in central and Eastern Europe. Value Health. 2010;13:289–97.

    Article  PubMed  Google Scholar 

  13. Viney R, Norman R, King MT, et al. Time trade-off derived EQ-5D weights for Australia. Value Health. 2011;14:928–36.

    Article  PubMed  Google Scholar 

  14. Lamers LM, McDonnell J, Stalmeier PF, et al. The Dutch tariff: results and arguments for an effective design for national EQ-5D valuation studies. Health Econ. 2006;15:1121–32.

    Article  CAS  PubMed  Google Scholar 

  15. Zarate V, Kind P, Valenzuela P, et al. Social evaluation of EQ-5D health states: the Chilean case. Value Health. 2011;14:1135–41.

    Article  PubMed  Google Scholar 

  16. Wittrup-Jensen KU, Lauridsen J, Gudex C, et al. Generation of a Danish TTO value set for EQ-5D health states. Scand J Public Health. 2009;37:459–66.

    Article  PubMed  Google Scholar 

  17. Norman R, Cronin P, Viney R, et al. International comparisons in valuing EQ-5D health states: a review and analysis. Value Health. 2009;12:1194–200.

    Article  PubMed  Google Scholar 

  18. Luo N, Chew LH, Fong KY, et al. Do English and Chinese EQ-5D versions demonstrate measurement equivalence? An exploratory study. Health Qual Life Outcomes. 2003;1:7.

    Article  PubMed Central  PubMed  Google Scholar 

  19. Luo N, Chew LH, Fong KY, et al. Validity and reliability of the EQ-5D self-report questionnaire in English-speaking Asian patients with rheumatic diseases in Singapore. Qual Life Res. 2003;12:87–92.

    Article  CAS  PubMed  Google Scholar 

  20. Luo N, Chew LH, Fong KY, et al. Validity and reliability of the EQ-5D self-report questionnaire in Chinese-speaking Asian patients with rheumatic diseases in Singapore. Ann Acad Med Singapore. 2003;32:685–90.

    CAS  PubMed  Google Scholar 

  21. Luo N, Low S, Lau PN, et al. Is EQ-5D a valid quality of life instrument in patients with Parkinson’s disease? A study in Singapore. Ann Acad Med Singapore. 2009;38:521–8.

    PubMed  Google Scholar 

  22. Gao, F, Ng GY, Cheung YB, et al. The Singapore English and Chinese version of the EQ-5D achieved measurement equivalence in cancer patients. J Clin Epidemiol. 2009;62:206–13.

    Google Scholar 

  23. Abdin E, Subramanian M, Vaingankar JA, et al. Measuring health-related quality of life among adults in Singapore: population norms for the EQ-5D. Qual Life Res. 2013;22(10):2983–91.

    Google Scholar 

  24. Wang YT, Lim HY, Tai D, et al. The impact of irritable bowel syndrome on health-related quality of life: a Singapore perspective. BMC Gastroenterol. 2012;12:104.

    Article  CAS  PubMed Central  PubMed  Google Scholar 

  25. Chong SA, Abdin E, Luo N, et al. Prevalence and impact of mental and physical comorbidity in the adult Singapore population. Ann Acad Med Singapore. 2012;41:105–14.

    PubMed  Google Scholar 

  26. Zhang XH, Li SC, Fong KY, et al. The impact of health literacy on health-related quality of life (HRQoL) and utility assessment among patients with rheumatic diseases. Value Health. 2009;12:S106–9.

    Article  PubMed  Google Scholar 

  27. Gold MR, Patrick DL, Torrance GW, et al. Identifying and valuing outcomes. In: Gold MR, Siegel JE, Russell LB, editors. Cost-effectiveness in health and medicine. New York: Oxford University Press; 1996. p. 82–134.

    Google Scholar 

  28. Samuelsen CH, Augestad LA, Stavem K, et al. Anchoring effects in the lead-time time trade-off. In: Proceedings of the 29th EuroQol Plenary Meeting, 13–15 Sept 2012. The Doelen Convert and Congress Hall, Rotterdam, The Netherlands.

  29. Liu G, Wu H, Sun L, et al. Chinese valuation of EQ-5D health states with the time trade-off method. Value Health. 2012;15:A650.

    Article  Google Scholar 

  30. Silvey SD. The lagrangian multiplier test. Ann Math Stat. 1959;30:389–407.

    Article  Google Scholar 

  31. Hausman J. Specification tests in econometrics. Econometrica. 1978;46:1251–71.

    Article  Google Scholar 

  32. Breusch T, Pagan A. A simple test of heteroskedasticity and random coefficient variation. Econometrica. 1979;47:1287–94.

    Article  Google Scholar 

  33. Shapiro SS, Wilk MB. An analysis of variance test for normality (complete samples). Biometrika. 1965;52:591–611.

    Article  Google Scholar 

  34. Fayers PM, Machin D. Quality of life: assessment, analysis and interpretation. 3rd ed. Chichester: Wiley; 2005.

    Google Scholar 

  35. Bland JM, Altman DG. Statistical method for assessing agreement between two methods of clinical measurement. Lancet. 1986;1:307–10.

    Article  CAS  PubMed  Google Scholar 

  36. Department of Statistics Singapore. Census of population 2010 statistical release 1: demographic characteristics, education, language and religion. http://www.singstat.gov.sg/publications/publications_and_papers/cop2010/census10_stat_release1.html. Accessed 15 Jul 2013.

  37. Devlin NJ, Tsuchiya A, Buckingham K, et al. A uniform time tradeoff method for states better and worse than dead: feasibility study of the ‘lead time’ approach. Health Econ. 2011;20:348–61.

    Article  PubMed  Google Scholar 

  38. Luo N, Li M, Stolk EA, et al. The effects of lead time and visual aids in TTO valuation: a study of the EQ-VT framework. Eur J Health Econ. 2013;14(Suppl 1):S15–24. doi:10.1007/s10198-013-0504-1.

    Article  PubMed  Google Scholar 

  39. Brazier J, Ratcliffe J, Salomon J, et al. Measuring and valuing health benefits for economic evaluation. Oxford: Oxford University Press; 2007.

    Google Scholar 

  40. Stalmeier PF, Lamers LM, Busschbach JJ, et al. On the assessment of preferences for health and duration: maximal endurable time and better than dead preferences. Med Care. 2007;45:835–41.

    Article  PubMed  Google Scholar 

  41. BMJ Group Blogs. BMJ Supportive & Palliative Care. “One can die, but cannot fall ill”. A Survey on how costs may affect choice of therapy in Singapore. http://blogs.bmj.com/spcare/2012/04/17/one-can-die-but-cannot-fall-ill-a-survey-on-how-costs-may-affect-choice-of-therapy-in-singapore/. Accessed 15 May 2013.

  42. Pakir A. Bilingual education with English as an official language: sociocultural implications. In: Alatis JE, Tan AH, editors. Georgetown University round table on languages and linguistics. Washington, DC: Georgetown University Press; 1999.

    Google Scholar 

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Acknowledgments

This study was funded by the National University of Singapore.

Contribution of Authors

Nan Luo designed the study; Pei Wang analyzed the data; Nan Luo and Pei Wang drafted the manuscript; and Julian Thumboo, Yee-Wei Lim and Hubertus Vrijhoef contributed the interpretation of the results and commented on and/or edited the drafts of the manuscript. Nan Luo acts as guarantor for the overall content.

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None.

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Correspondence to Nan Luo.

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Luo, N., Wang, P., Thumboo, J. et al. Valuation of EQ-5D-3L Health States in Singapore: Modeling of Time Trade-Off Values for 80 Empirically Observed Health States. PharmacoEconomics 32, 495–507 (2014). https://doi.org/10.1007/s40273-014-0142-1

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