Determinants of equitable public health human resource allocation in China: a multidimensional analysis using RIF-I-OLS decomposition.

BACKGROUND: Rapid economic development and urbanization in China have improved population health outcomes, but exacerbated inequalities in the allocation of public health human resources (PHHR). Existing studies largely rely on static measures and offer limited insights into the mechanisms driving these disparities. This study systematically identifies and quantifies the determinants influencing public health workforce allocation in China, aiming to provide empirical evidence to guide policy interventions. METHODS: This study analyzed the allocation of PHHR across 31 Chinese provinces from 2018 to 2022, employing four inequality indices: Gini coefficients (Gini), concentration index (CI), absolute Gini (AGini), and absolute concentration index (ACI). Two-way analysis of variance (ANOVA) and bivariate correlation analyses were used to assess temporal and regional variations. The recentered influence function-index-ordinary least squares (RIF-I-OLS) method was applied to decompose these inequality indices. This approach quantified the contributions of key factors, including the illiteracy rate among the population aged 15 years and above, government health expenditure, number of professional public health institutions (PPHI), mortality rate from Class A and B infectious diseases (IDs), and life expectancy (LE), while distinguishing between characteristic effects and coefficient effects. RESULTS: Between 2018 and 2019, inequity in PHHR allocation increased (Gini: 0.3792-0.3844; CI 0.0215-0.0495). In contrast, from 2019 to 2022, allocation equity improved (Gini: 0.3715; CI 0.0279). A greater number of PPHIs, a lower mortality rate of class A and B IDs, and longer LE helped mitigate inequalities, whereas a lower illiteracy rate among the population aged ≥ 15 years and increased governmental health expenditure exacerbated disparities. Inequality in PHHR allocation during 2018-2019 was primarily driven by characteristic effects, whereas in 2021-2022, coefficient effects became dominant, underscoring the role of institutional and systemic factors. CONCLUSIONS: While the equity of PHHR allocation in China has shown modest improvement, structural and institutional factors remain key determinants of lingering inequities. This highlights the need for targeted policies to optimize the distribution of the public health workforce.