Ortendahl Monica, Fries James F
Stanford University School of Medicine, Department of Medicine, Division of Immunology and Rheumatology, 1000 Welch Road, Suite 203, Palo Alto, CA 94304, USA.
J Clin Epidemiol. 2006 Nov;59(11):1222-7. doi: 10.1016/j.jclinepi.2005.12.018. Epub 2006 Aug 24.
To review intertemporal choices, involving decisions with a trade-off between something now and something later. These choices are common in health both at an individual and societal level.
The present value of an outcome, for example, the amount of money or the health outcomes in various aspects, is equivalent to the value of a future outcome discounted with the delay of time. The concept of diminishing value over time is positive discounting. Economic forecasts generally use discount rates in which the value of a future dollar is less than the value of a present dollar, and where the discount rates are similar for the individual investor and society. The value of future health is commonly thought of as similar to the value of future money. Yet, the individual may rationally choose a discount rate that is exceedingly low or even negative. This paradox is particularly relevant when considering primary and secondary prevention, where initial and continuing costs may precede beneficent outcomes by decades, making discount rate selections the dominant factor in determining decisions.
We suggest that the societal perspective should also recognize that discount rates for health outcomes are largely irrelevant and that even negative discount rates have crucial relevance.
回顾跨期选择，即涉及在当下的事物与未来的事物之间进行权衡的决策。这些选择在健康领域的个人和社会层面都很常见。
一个结果的现值，例如金钱数额或各个方面的健康结果，等同于一个未来结果经过时间延迟后的贴现价值。随着时间推移价值递减的概念就是正贴现。经济预测通常使用贴现率，其中未来一美元的价值低于当前一美元的价值，并且个体投资者和社会的贴现率相似。未来健康的价值通常被认为与未来金钱的价值相似。然而，个体可能理性地选择一个极低甚至为负的贴现率。当考虑一级和二级预防时，这个悖论尤其相关，因为初始和持续成本可能在数十年后才会产生有益结果，使得贴现率的选择成为决定决策的主导因素。
我们建议社会视角也应认识到健康结果的贴现率在很大程度上无关紧要，甚至负贴现率也具有至关重要的相关性。
