Unequal roles of cities in the intercity healthcare system

Cities are increasingly interdependent regarding healthcare provision and demand. However, the intercity healthcare system (IHS) behind the nationwide patient mobility remains insufficiently understood. Here, leveraging human mobility big data, we reveal cities' roles in providing and demanding quality healthcare within the IHS of China. We find that 8% of Chinese cities are national and regional hubs that address the healthcare shortage of cities deprived of quality healthcare, while 63% of the cities that are unnoticed compensate for migrant workers being denied healthcare rights in megacities. The IHS generates new structural inequalities in healthcare access exhibiting a Matthew effect. The few cities (12%) that are already rich in healthcare resources benefit more and can strengthen their advantages in providing healthcare to local populations (32% of China's total population). The many cities (35%), while facing healthcare shortages, are further disadvantaged in ensuring adequate healthcare for their local populations (26% of China's total population). This study used cell phone data to estimate patient mobility, defined as individuals seeking healthcare in cities other than their city of residence, in China. It found that the three types of patient mobility interweave to form an intercity healthcare system and produce new structural inequalities in local quality healthcare provision among cities.