How much do socioeconomic inequalities explain gender- and ethnicity-based gaps in health coverage? A decomposition analysis of Chinese migrant workers, 2009–2018

Health coverage equality is key to equal healthcare access. In China, the Urban Employee Basic Medical Insurance (UEBMI) is a compulsory health coverage for people employed in urban areas and provides the best access to healthcare. Having the UEBMI is thus crucial for rural-to-urban migrant workers, the lack thereof indicates not only informal employment, but also unequal healthcare access, particularly for their vulnerable subgroups. This study aims to explore factors that contribute to UEBMI coverage gaps between gender and ethnicity migrant worker subgroups. The findings provide insights on targeted social policies to reduce inequalities in the most vulnerable subgroups. Using the population-based, nationally representative data from the China Migrant Dynamics Survey from 2009 to 2018, we assessed the UEBMI coverage rate status gaps in China’s migrant worker gender and ethnic subgroups. Socioeconomic determinants were education level, household income and occupation. Using probit regression models, we applied the Oaxaca-Blinder decomposition method to examine the extent to which gender and ethnicity disparities could be explained by socioeconomic gradients in UEBMI coverage rate status. One million, one hundred ninety-nine thousand, and thirteen participants were included in our study, 46.9% (n = 561 808) were women, 7.8% (n = 93 934) were of ethnic minority group, and average age was 34.6 (± 10.2) years. Women (16.67%, 95% CI [16.54 – 16.79]) showed higher UEBMI coverage than men (15.93%, 95% CI [15.83 – 16.03]), and ethnic minority showed lower coverage rate (12.09%, 95% CI [11.85 – 12.34]) than Han majority (16.59%, 95% CI [16.50 – 16.67]). Decomposition analysis indicated education was the major contributor to the UEBMI differences between gender and ethnicity groups. Having a Bachelor’s degree was the major contributor. If the subgroups had equally attained Bachelor’s degree education, the coverage gap would enlarge between men and women by 66.87%, but the coverage gap would be reduced between ethnic minority and Han majority groups by 17.57%. Age and occupation type were the major contributors in UEBMI differences between men and women; living in western region would close the UEBMI gap between ethnic minority and Han majority groups. Our study found differences in UEBMI coverage rate status between Chinese migrant worker gender and ethnicity subgroups. Our findings contribute to targeted policy strategies to enhance UEBMI coverage equality, thereby reducing healthcare access inequalities in rural-to-urban migrant worker subgroups.