The disparity in life expectancy between white and black Americans exceeds five years for men and three years for women. While prior research has investigated the roles of healthcare, health behaviors, biological risk, socioeconomic status, and life course effects on black mortality, the literature on the geographic origins of the gap is more limited. This study examines how the black–white life expectancy gap varies across counties and how much of the national gap is attributable to within‐county racial inequality versus differences between counties. The estimates suggest that over 90 percent of the national gap can be attributed to within‐county factors. Using a quasi‐experimental research design, I find that black–white residential segregation increases the gap by approximately 16 years for men and five years for women. The segregation effect loads heavily on causes of death associated with access to and quality of healthcare; safety and violence; and public health measures. Residential segregation does not appear to operate through health behaviors or individual‐level factors but instead acts primarily through institutional mechanisms. Efforts to address racial disparities in mortality should focus on reducing racial residential segregation or reducing inequalities in the mechanisms through which residential segregation acts: public services, employment opportunities, and community resources.

中文翻译：

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黑人与白人的预期寿命差距从何而来？居住隔离的致命后果

美国白人和黑人的预期寿命差距男性超过五年，女性超过三年。虽然之前的研究已经调查了医疗保健、健康行为、生物风险、社会经济地位和生命历程对黑人死亡率的影响，但有关差距地理起源的文献更为有限。这项研究探讨了各县之间黑人与白人预期寿命差距的差异，以及全国差距在多大程度上归因于县内种族不平等与县间差异。据估计，超过 90% 的全国差距可归因于县内因素。通过准实验研究设计，我发现黑人与白人的居住隔离使男性的差距增加了约 16 岁，女性的差距增加了 5 岁。隔离效应严重影响与医疗保健的获取和质量相关的死亡原因；安全和暴力；和公共卫生措施。居住隔离似乎并不是通过健康行为或个人层面的因素来发挥作用，而是主要通过制度机制发挥作用。解决死亡率方面的种族差异的努力应集中于减少种族居住隔离或减少居住隔离发挥作用的机制中的不平等：公共服务、就业机会和社区资源。