Income-related inequality in health outcomes among older individuals in China: A measurement and decomposition analysis
Population aging in China presents a significant challenge, with projections indicating that individuals aged 65 and above will exceed 30% of the total population by 2050, thereby increasing health-care and long-term care (LTC) demands. Therefore, this study aimed to examine income-related inequality in self-rated health (SRH) and functional ability among older individuals in China while also examining the contribution of socioeconomic factors to health inequality. Data were drawn from the 2018 wave of the Chinese Longitudinal Healthy Longevity Survey. Well-established tools, such as concentration curves, the Erreygers concentration index (EI), and decomposition analysis, were employed to elucidate income-related inequality in health within the sample. The results revealed that for SRH, both unstandardized and standardized concentration curves were observed below the 45° line, with unstandardized EI at 0.068 and standardized EI at 0.033. For functional ability, both unstandardized and standardized concentration curves were observed above the 45° line, with unstandardized EI at −0.016 and standardized EI at −0.003. These results suggest that, after controlling for demographic factors, the better-off group is more likely to report better SRH and less likely to experience functional limitations compared to the worse-off group. Furthermore, this inequality in health outcomes is predominantly driven by socioeconomic factors rather than demographic factors. For SRH, income emerges as the primary contributor to total inequality. Similarly, for functional ability, income emerges as the key factor driving inequality, disproportionately affecting the less affluent population. Consequently, it is crucial for the government to protect older individuals with lower socioeconomic status to mitigate income-related inequality in health by directly providing cash aids and formal LTC, which could contribute to promoting healthy aging in the context of global aging.
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