Spatial networks of China's specialized, refined, distinctive, and innovative medical device firms based on parent–subsidiary contacts: implications for regional health policy

This study examines the spatial structure and determinants of China's specialized, refined, distinctive, and innovative (SRDI) medical device industry through parent-subsidiary linkages. By combining social network analysis and geographical detectors, we analyze nationwide firm-level data from Qixinbao to explore network connectivity, centrality, and their socioeconomic drivers. The results show that (1) the overall network connectivity among Chinese cities is weak, with clear east-west disparities and Shanghai, Guangzhou, Beijing, and Shenzhen functioning as core hubs; (2) four distinct network subgroups exist, each assuming different roles in information and resource diffusion; and (3) factors such as economic base, degree of openness, and technological innovation are strongly associated with variations in network centrality across cities. These findings highlight the uneven spatial organization of China's SRDI medical device industry and underline the importance of strengthening interregional linkages, supporting innovation ecosystems, and improving talent and trade openness in less-developed regions. The study contributes to the literature by combining network analysis with spatial heterogeneity detection, offering empirical evidence for more balanced regional health industry development.