Measuring supply–demand coupling coordination in China’s older adult care services: spatiotemporal evolution, spatial spillover effects, and driving factors based on the spatial Durbin model

The coordinated development of older adult care service resource supply and the needs of older adults is not only pivotal for advancing the construction of China’s older adult care service system and improving the social security framework, but is also essential for the effective implementation of the national strategy for actively addressing population aging. However, a structural imbalance currently exists between older adult care service supply and the needs of older adults, with pronounced developmental disparities across the eastern, central, and western regions, underscoring an urgent need for in-depth analysis of the evolutionary patterns of supply–demand coordination and its spatial transmission mechanisms from a systems coupling perspective. This study theoretically transcends the conventional paradigm of unidirectional supply-side or demand-side analysis by constructing an analytical framework for supply–demand coordination in older adult care services from a systems coupling perspective, thereby extending the application boundaries of coupling coordination theory to the social services domain; empirically, it employs multiple spatial econometric methods to systematically reveal the spatiotemporal evolutionary patterns, spatial agglomeration characteristics, and regionally heterogeneous driving mechanisms of the supply–demand coupling coordination degree, providing a quantitative basis for the scientific formulation of differentiated older adult care policies.

Based on panel data from 31 provinces and municipalities in China spanning 2014 to 2023, the entropy weight method was applied to measure supply and demand levels, the coupling coordination degree model was employed to evaluate the level of coordinated development, Moran’s Index was used to characterize spatial agglomeration features, and a spatiotemporal dual fixed-effects Spatial Durbin Model was constructed to analyze the direct, indirect, and total effects of the influencing factors.

The findings indicate that the supply–demand coupling coordination degree of older adult care service resources in China has followed a steadily upward yet slowly progressing trend, remaining at an overall low level of coordination. Significant regional differentiation is evident, manifesting as a spatial pattern of “high in the east, low in the west,” with this divergence continuously intensifying. Significant spatial autocorrelation has given rise to relatively stable high–high and low–low clustering zones, reflecting that the structural imbalance between supply and demand constitutes the fundamental constraint on coordinated development. Multi-dimensional driving factors — including population aging, economic development, and fiscal investment — exhibit marked regional heterogeneity in their effects on the coupling coordination degree, with considerable differences in development dynamics across regions.

Older adult care service resources display a structural imbalance in which supply quality lags behind the upgrading of demand. The eastern region maintains a relative lead in coupling coordination, the central region is in a phase of steady catch-up, and the western region continues to face fundamental bottlenecks. Each region should, in accordance with its own stage of development and regional characteristics, pursue differentiated supply–demand coordination pathways by optimizing fiscal investment structures, establishing regional vertical cooperation mechanisms, and implementing targeted reforms in resource allocation, so as to effectively advance the dynamic equilibrium between older adult care service supply and the needs of older adults.