Promoting sustainable health equity: accessibility analysis and optimization of tertiary hospital networks in China’s metropolitan areas

Healthcare accessibility is vital for sustainable urban development, ensuring timely diagnosis, chronic disease management, and emergency response. However, in many developing countries, the uneven distribution of advanced healthcare services exacerbates health disparities. Taking Tianjin in China as an example, this study aims to evaluate the spatial accessibility of tertiary hospitals and optimize hospital placement to improve healthcare coverage. Using the Gaussian Two-Step Floating Catchment Area (G2SFCA) method, the study integrated high-resolution spatial data on hospital locations, population density, and transportation networks, assessing the accessibility of higher-level healthcare services citywide. The results indicate that central urban districts exhibited high accessibility, where all demand points were within the 1-hour service range. In contrast, suburban districts had an average accessibility of 0.194, and outer suburban districts had the lowest citywide mean of 0.005, with less than 20% of the area covered. Despite its economic significance, Binhai New Area’s healthcare accessibility remained inadequate, with a mean score of 0.010. The application of a location-allocation model to optimize the placement of 24 planned new hospitals, prioritizing areas with high population density and low accessibility resulted in an increased population coverage from 73.31% to 95.05%, significantly reducing non-accessible points. This study aligns with the United Nations’ Sustainable Development Goals 3 and 11, advocating a hierarchical healthcare system, telemedicine, and improved transportation to minimize time costs and reduce inequities.