Health Utility Value Measurement Research

Health is a permanent goal pursued by the people. How to take advantage of limited resources to meet the health demands confronting every country, and is a more serious problem for China where more population and less per capita resources. Economic evaluation for different health interventions provides the guideline and reference for allocating resources reasonably. The decision makers could make the optimal choice through comparing the inputs and the outputs among variety interventions. The monetary indicator (benefit), clinical end-point (effectiveness) or quality adjusted life years (utility) are the three types of outcome indicators to refer to the outputs, which standing for cost-benefit analysis (CBA), cost-effectiveness analysis (CEA), and cost-utility analysis (CUA), respectively. QALYs is a general comparable indicator, which combines the actual improvements of health and the subjective perception, so CUA is the most important approach and recommended to be used by many countries.Health utility refers to the preference for a particular health state, which is a quantitative index for quality of life to calculate the QALYs. Direct and indirect measurement can be used to obtain this index. The first method including visual analogue scale (VAS), time trade-off (TTO), and standard gamble (SG), etc. Establishing the value set for a health-related quality of life instrument is critical to indirect measurement method. Because health utility refers to the preferences, people from different countries with different culture systems and outlooks of value and economic development levels would have different preferences to the same health state. Therefore, the value set based on the local population preferences should be used in making health decisions.Through systematic literature review, this paper finds that there are few studies about health utility measurement and the research scope is narrow relatively. Most of the existing studies focus on theoretical introduction and discussion on some direct measurements and empirical study on small or specific population. Thus, the application of CUA is restricted in China due to the lack of deeply research on health utility measurement. In view of imperious demands as well as the important practical significance of obtaining health utility in an accurate, convenient and effective way, this paper gives a comprehensive introduction and analysis to the main measurement methods and how to develop the value set. Then, the Chinese tariff for EQ-5D is developed based on the experiences of previous studies. This article also investigates the influencing factors affected valuations.Direct measurement method is overloaded and time expended. Respondents with high capacity of understanding and cooperation are required in practice when direct method used. However, indirect measurement method is more feasible than direct measurement method if there are large respondents in study. The basic thinking of value set development is to obtain valuations for some health states from a representative sample, and then construct model to predict valuations for all the health states. Because of lacking studies about health utility measurement, especially about how to obtain the value set, the comprehensive introduction and analysis to the main measurement methods and how to develop the value set are gave at the beginning of this article.Applications of direct measurements including in developing the value set, and how to obtain the value set is critical to indirect measurement, so the research focus of this paper is to analysis the experiences of previous studies and establish the local value set. HUI mark2, SF-6D, EQ-5D and two disease-specific instruments are the objects of this paper. The details about the steps of value set construction and the results are introduced, which would provide the important references for the following empirical study in this research. The problems about establishing value set are also discussed.Theory must not be divorced from practice. This paper chooses the EQ-5D as the object of empirical study. Utility values for a subset of97health states defined by the EQ-5D descriptive system are directly elicited by applying TTO technique. Econometric model is used to predict utility values of all health states. The total sample is1222general population selected by quota sampling. The results demonstrate that the N3model based on OLS regression at the aggregate level yielded the best predictive ability, with an adjusted R2of0.988, a mean absolute error (MAE) of0.020,7and0prediction errors greater than0.05and0.1respectively in absolute magnitude. In addition, the respondent’s characteristics including age, gender, etc. whether affecting the evaluations of health utility values or not are also investigated in this paper. The results show that the habits of physical exercise and age etc. are the influencing factors. But on the whole, the degree of influences is small. This study successfully develops Chinese utility weights for EQ-5D by applying TTO technique, base on representative population sample in China, and which is the first attempt ever to derive social value set for HRQoL instrument in China. But the limitations need to be further improved.