Background: A growing body of literature has reported widening educational health disparities across birth cohorts or time periods in the United States, but research has paid little attention to the implication of mortality selection on the cohort trend in health disparities. Objective: This study investigates how changes in the variance of unobserved frailty over time may complicate the interpretation of cohort trends in health disparities and life expectancy. Methods: We use the microsimulation method to test the effect of mortality selection and further propose a counterfactual simulation procedure to estimate its contribution. Data used in the simulations are based on Panel Studies of Income Dynamics 1968–2013, National Health and Nutrition Examination Survey data 1999‒2012, and National Health Interview Survey data 1986‒2011. Results: Simulation shows that mortality selection may generate seemingly contradictory trends in health disparities and life expectancy across birth cohorts at the group and individual level. Life expectancy can change even when the individual mortality curve is fixed. In the absence of a change in the causal effect of education on mortality at the individual level, an educational life expectancy gap can change across cohorts as a result of the change in frailty variance. Empirical analysis shows that mortality selection accounts for a sizeable amount of contribution to the widening educational life expectancy gap from the 1950s to 1960s birth cohorts in the United States. Contribution: We demonstrate how mortality selection can complicate the cohort trend in health disparities and life expectancy and propose a counterfactual simulation method to evaluate its contribution.

中文翻译：

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未观察到的人口异质性和健康差异的动态


背景：越来越多的文献报道美国不同出生队列或不同时期的教育健康差异不断扩大，但研究很少关注死亡率选择对健康差异队列趋势的影响。目的：本研究调查了随着时间的推移，未观察到的衰弱方差的变化如何可能使健康差异和预期寿命的队列趋势的解释复杂化。方法：我们使用微观模拟方法来测试死亡率选择的效果，并进一步提出反事实模拟程序来估计其贡献。模拟中使用的数据基于 1968-2013 年收入动态面板研究、1999-2012 年国家健康和营养检查调查数据以及 1986-2011 年国家健康访谈调查数据。结果：模拟表明，死亡率选择可能会在群体和个人层面上产生不同出生队列的健康差异和预期寿命看似矛盾的趋势。即使个人死亡率曲线固定，预期寿命也会发生变化。在教育对个体死亡率的因果影响没有发生变化的情况下，由于衰弱方差的变化，不同群体之间的教育预期寿命差距可能会发生变化。实证分析表明，死亡率选择对美国 20 世纪 50 年代至 1960 年代出生群体的教育预期寿命差距扩大有很大影响。贡献：我们展示了死亡率选择如何使健康差异和预期寿命的队列趋势复杂化，并提出了一种反事实模拟方法来评估其贡献。