A study on factors influencing and optimisation strategies for the distribution of medical facilities across all age groups in China from the perspective of spatial justice

Achieving universal health coverage for populations of all ages is a key objective of the Healthy China 2030 strategy. However, optimising the supply-demand balance of healthcare facilities and resources to ensure equitable allocation across age groups remains a major challenge. This study examines the spatial equity of healthcare facilities for different age cohorts and explores the factors shaping these spatial patterns. An improved Maximum Accessibility Equality model (Palma-MAE) was applied to evaluate the spatial equity of healthcare facilities. The Standard Deviation Ellipse (SDE) method was used to analyse spatial distribution patterns of healthcare spatial equity across different age groups. In addition, a Multi-Scale Geographically Weighted Regression (MGWR) model was employed to identify the key factors influencing spatial equity in healthcare facilities among different age cohorts. Among all age groups, the 15–59 age group exhibited the highest level of spatial equity in access to healthcare facilities, followed by the 60–64 and \(≥\) 65 age groups, while the 0–14 age group showed the lowest level. Spatially, areas approaching equity were more widely distributed for the 0–14 and 60–64 age groups, whereas more complex spatial patterns were observed for the 15–59 and \(≥\) 65 age groups. Demographic, social, and economic factors exerted different influences across age groups. For the 0–14 age group, spatial equity was mainly associated with population density, population ageing, natural population growth rate, educational attainment, per capita disposable income, and fiscal self-sufficiency. For the 15–59 age group, urbanisation rate, educational attainment, per capita disposable income, population ageing, natural population growth rate, and fiscal self-sufficiency were key influencing factors. For the elderly age groups (60–64 and \(≥\) 65), spatial equity was primarily influenced by the proportion of non-agricultural industries, fiscal self-sufficiency, per capita GDP, population ageing, natural population growth rate, and disposable income. Substantial regional disparities exist in the spatial equity of healthcare facilities across different age groups. Optimising healthcare resource allocation should therefore account for the heterogeneous healthcare needs of different age cohorts shaped by demographic, social, and economic conditions. These findings provide evidence to support more equitable and efficient allocation of public healthcare resources.