, Volume 32, Issue 5, pp 495–507 | Cite as

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

  • Nan Luo
  • Pei Wang
  • Julian Thumboo
  • Yee-Wei Lim
  • Hubertus J. M. Vrijhoef
Original Research Article



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.


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.


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.


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.


Valuation Study Random Effect Ordinary Less Square Estimator Indifference Point Prediction Precision 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



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.

Conflicts of Interest



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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Nan Luo
    • 1
  • Pei Wang
    • 1
  • Julian Thumboo
    • 2
    • 3
  • Yee-Wei Lim
    • 1
  • Hubertus J. M. Vrijhoef
    • 1
  1. 1.Saw Swee Hock School of Public Health, National University of Singapore and National University Health SystemSingaporeSingapore
  2. 2.Department of Rheumatology and ImmunologySingapore General HospitalSingaporeSingapore
  3. 3.Department of MedicineNational University Health SystemSingaporeSingapore

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