Modeling Spatial Accessibility of Healthcare Services for the Elderly Population with a SAM-G2SFCA Method: A Resource-Sharing Perspective

Accessibility of healthcare services is a paramount determinant of elderly health outcomes. However, existing research often neglects the effects of resource-sharing pressures among different demographic groups for healthcare resources when measuring the accessibility for elderly population. To bridge this gap, this study developed a Supply Allocation Model (SAM) that considers the interactions between the elderly and non-elderly populations, as well as the distribution of healthcare resources. The model was subsequently integrated with the G2SFCA method, utilizing demographic, mobile phone, and point of interest (POI) datasets to assess the spatial accessibility of healthcare services for the elderly population in Guangzhou, China. The model’s accuracy and reliability were tested through calibration and validation processes, utilizing real-world healthcare treatment datasets. The effectiveness of the SAM was measured through the computation of the healthcare accessibility index and the Gini coefficient, utilizing both the SAM-G2SFCA and G2SFCA models. The results show that the SAM achieves the highest prediction accuracy at a 15-minute threshold. As the time threshold decreases, the role of supply factors in predicting the proportion of healthcare utilization strengthens. Moreover, the SAM-G2SFCA leads to a reduction in the equity of accessibility across all time thresholds when compared to the G2SFCA method, particularly in peripheral urban areas where elderly populations face greater resource-sharing pressures and healthcare accessibility is often overestimated. These findings provide valuable insights for policy formulation and theoretical advancement, informing the design of more equitable and efficient healthcare resource allocation strategies.