Harvard T.H. Chan School of Public Health, Boston, MA, 02115, USA.
Naval Postgraduate School, Monterey, CA, 93943, USA.
Risk Anal. 2021 May;41(5):761-770. doi: 10.1111/risa.13561. Epub 2020 Jul 16.
Numerous analyses of the benefits and costs of COVID-19 policies have been completed quickly as the crisis has unfolded. The results often largely depend on the approach used to value mortality risk reductions, typically expressed as the value per statistical life (VSL). Many analyses rely on a population-average VSL estimate; some adjust VSL for life expectancy at the age of death. We explore the implications of theory and empirical studies, which suggest that the relationship between age and VSL is uncertain. We compare the effects of three approaches: (1) an invariant population-average VSL; (2) a constant value per statistical life-year (VSLY); and (3) a VSL that follows an inverse-U pattern, peaking in middle age. We find that when applied to the U.S. age distribution of COVID-19 deaths, these approaches result in average VSL estimates of $10.63 million, $4.47 million, and $8.31 million. We explore the extent to which applying these estimates alters the conclusions of frequently cited analyses of social distancing, finding that they significantly affect the findings. However, these analyses do not address other characteristics of COVID-19 deaths that may increase or decrease the VSL estimates. Examples include the health status and income level of those affected, the size of the risk change, and the extent to which the risk is dreaded, uncertain, involuntarily incurred, and outside of one's control. The effects of these characteristics and their correlation with age are uncertain; it is unclear whether they amplify or diminish the effects of age on VSL.
针对 COVID-19 政策的利弊已经进行了大量分析,因为这场危机正在展开。结果往往在很大程度上取决于用于衡量死亡率降低的方法,通常用每统计生命的价值(VSL)来表示。许多分析依赖于人口平均 VSL 估计值;有些则根据死亡时的预期寿命调整 VSL。我们探讨了理论和实证研究的含义,这些研究表明年龄与 VSL 之间的关系不确定。我们比较了三种方法的影响:(1)不变的人口平均 VSL;(2)每统计生命年的固定价值(VSLY);(3)遵循倒 U 型模式的 VSL,在中年达到峰值。我们发现,当将这些方法应用于 COVID-19 死亡的美国年龄分布时,它们导致平均 VSL 估计值分别为 1063 万美元、447 万美元和 831 万美元。我们探讨了这些估计值应用于经常引用的社会隔离分析结论的程度,发现它们会显著影响这些发现。然而,这些分析并没有解决 COVID-19 死亡的其他特征,这些特征可能会增加或降低 VSL 估计值。例如,受影响者的健康状况和收入水平、风险变化的大小以及风险被恐惧、不确定、非自愿承担和超出控制的程度。这些特征的影响及其与年龄的相关性是不确定的;不清楚它们是否会放大或缩小年龄对 VSL 的影响。