Impacts of high-speed rail on intercity patient mobility: evidence from chronic kidney disease hospitalization in China

Due to the growing demand for high-quality healthcare and the uneven medical resources distribution, intercity patient mobility has become prevalent. The recent transportation advancements, particularly high-speed rail (HSR), has been proved to facilitate intercity mobility, yet its effects on patient mobility remain unclear. To bridge this gap, this study examines the impacts of HSR on intercity patient mobility using 4 million records of national chronic kidney disease (CKD) hospitalization in China. Based on difference-in-differences models, OLS regression and yearly regression, we find that: (1) HSR implementation increases intercity patient flows by 8.24 ± 3.28%, with 28.51 ± 6.26% more flows when HSR travel speed is twice of conventional rails and 11.8% ± 0.33% more flows when the number of available trains doubles. (2) HSR boosts flows to megacities and large cities by 23.02 ± 11.57% and 7.26 ± 4.26%, respectively, while having no significant effects on small cities. (3) Three years after HSR implementation, the effect in megacities turns negative, while remaining positive and growing in magnitude in large cities. Our findings demonstrate that HSR not only influences the volume of intercity patient mobility but also reshapes its spatial patterns. These insights underscore the need to invest in advanced transportation technologies and to promote coordinated decision-making across healthcare, transportation, and urban development policies.