2000~2021年高、中收入国家的人口因素在人均GDP与婴儿死亡率间的中介效应分析

Analysis of the Mediating Effect of Demographic Factors on the Relationship between per Capita GDP and Infant Mortality Rate in High- and Middle-Income Countries from 2000 to 2021

摘要: 目的：论证人均GDP通过人口因素影响婴儿死亡率的间接作用。方法：基于世界银行数据库的更新数据，以2000~2021年高、中收入国家的婴儿死亡率为因变量，人均GDP为自变量，分别以总生育率、人口密度、超百万城市群的人口、人口增长、城镇人口增长率为中介变量，进行中介效应分析。结果：在高收入国家，总生育率发挥部分中介效应，人口密度的中介效应不显著，超百万城市群的人口、人口增长、城镇人口增长率均发挥遮掩效应。在中收入国家，总生育率、人口增长、城镇人口增长率均发挥部分中介效应，人口密度、超百万城市群的人口均发挥遮掩效应。各中介模型的直接效应均显著。结论：人口因素的中介效应存在收入国家异质性。建议持续发挥经济发展的主导作用，同时因地制宜优化人口政策。

Abstract: Objective: To demonstrate the indirect effect of per capita GDP on infant mortality rate through demographic factors. Methods: Based on updated data from the World Bank database, an intermediary effect model was constructed with infant mortality rate in high- and middle-income countries from 2000 to 2021 as the dependent variable and per capita GDP as the independent variable. Total fertility rate, population density, population in urban agglomerations with over one million people, population growth, and urban population growth rate were used as mediating variables, respectively. Results: In high-income countries, the total fertility rate played a partial mediating effect, while the mediating effect of population density was not significant. Population in urban agglomerations of over one million, population growth, and urban population growth rate all played a masking effect. In middle-income countries, total fertility rate, population growth, and urban population growth rate all played a partial mediating effect, while population density and population in urban agglomerations of over one million played a masking effect. The direct effects of each mediation model were significant. Conclusion: The mediating effects of demographic factors vary across income groups. It is recommended to sustain the leading role of economic development while adopting context-specific population policies.