Time Trade-Off Value Set for EQ-5D-3L Based on a Nationally Representative Chinese Population Survey

To obtain a nationally representative Chinese three-level EuroQol five-dimensional questionnaire value set based on the time trade-off (TTO) method.

A multistage, stratified, clustered random nationally representative Chinese sample was used. The study design followed an adapted UK Measurement and Valuation of Health protocol. Each respondent valued 11 random states plus state 33333 and "unconscious" using the TTO method in face-to-face interviews. Three types of models were explored: ordinary least squares, general least squares, and weighted least squares models.

In total, 5939 inhabitants aged 15 years and older were interviewed. Of these, 5503 satisfactorily interviewed participants were included in constructing models. An ordinary least squares model including 10 dummies without constant and N3 had a mean absolute error of 0.083 and a correlation coefficient of 0.899 between the predicted and mean values. Goodness-of-fit indices of two models based on split subsample were similar.

TTO values were higher in our study compared with those in a study carried out in urban areas, which is mirrored by the higher values in rural areas. Several other aspects, in addition to the valuation procedure, might have influenced the results, such as factors beyond demographic factors such as view on life and death and believing in an afterlife, which need further investigation. Future studies using the three-level EuroQol five-dimensional questionnaire should consider using this value set based on a nationally representative sample of the Chinese population.