Integration of Quality of Life and Survival for Comparative Risk/Outcome Assessment in Healthcare Industry
Survival and quality of life (QOL) are two key measurements for outcome evaluation in health care services. While the former can be objectively determined, the latter can only be obtained from subjective reports of the patients with specific health conditions. Considering these two outcome functions together can derive a universal equation in healthcare evaluation with quality-adjusted life year (QALY) as the common unit, when the QOL is measured in utility or preference. Because many patient cohorts are only followed for a limited period of time with a high censored rate or above 50%, we have developed a Monte Carlo method that borrows information from age- and sex- matched general population for extrapolation of survival function to life time. By doing so, we are able to simultaneously quantify the years of life expectancy loss for a specific health condition. When the QOL function is measured by psychometric instruments, the resulted score-time can be used on outcome evaluation on clinical medicine; when the QOL function is replaced by medical cost reimbursed by the National Health Insurance, we can obtain the lifetime financial burden for a specific health condition; both developments can be used for comparative outcome assessment in health care services. Empirical examples are provided as a demonstration of feasibility.
The objective of this chapter is to introduce a novel method of integration between survival and quality of life functions and illustrate how it can be directly applied for comparative health risk and clinical outcome assessments. We shall begin with the original concept of quantifying the burden of diseases, followed by deriving the equation for health, application of such methods for health risk assessment in three different settings, extension of the QOL measurement to psychometry and estimation of lifetime medical costs.
KeywordsSurvival Function Health Risk Assessment Specific Health Condition Life Expectancy Loss Lifetime Medical Cost
List of Abbreviations:
acquired immunodeficiency syndrome
disability-adjusted life year
human immunodeficiency virus
National Health Insurance
National Insurance System
quality-adjusted life expectancy
quality-adjusted life month
quality-adjusted life year
quality-adjusted survival time
quality of life
reasonable maximum exposure
World Health Organization quality of life
I am most grateful to my respected colleagues, including Grace Kaiping Yao (Department of Psychology, NTU), Jin-Tan Liu (Department of Economics, NTU), and all the faculty and students of both College of Public Health and College of Medicine of the National Taiwan University for their kind assistance and support in the development of the above research and the National Health Research Institutes for funding the research (No. NHRI-EX95–9204PP).
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