The "Iron Triangle" of Healthcare Services: Evaluating an Integrated Healthcare Alliance's Impact on Primary Care in Shenzhen, China.

Introduction: In response to the challenges of inequitable healthcare access and underdeveloped primary care systems, integrated care reforms have emerged as a promising solution. This study examines the effectiveness of one such reform, i.e. the establishment of a cross-regional, tightly integrated healthcare alliance (specifically an urban healthcare group) in the resource-constrained Dapeng District of Shenzhen, China. We assess its impact on service delivery performance through the lens of three core health system objectives: accessibility, quality, and affordability. Methods: We utilised longitudinal data from 2012 to 2023 and defined seven indicators aligned with the three core health system goals: accessibility, quality, and affordability. Both annual and quarterly data were used, with quarterly data applied to the interrupted time-series analysis. We employed an interrupted time-series analysis (ITSA) to estimate both immediate level changes and subsequent slope changes in the trends. Serial autocorrelation was assessed using the Durbin-Watson (DW) test. Where autocorrelation existed, we used Prais-Winsten generalised least squares (GLS) to ensure robust estimation. Furthermore, we analysed bidirectional referral data to corroborate the effectiveness of the hierarchical diagnosis and treatment system. We also incorporated per-capita medical expenditure, drawn from district administrative records, to track affordability trends over time. Results: The reform was associated with significant improvements across quality, accessibility, and affordability. The capacity of local healthcare institutions to manage severe and complex conditions was substantially enhanced, reflected in significant post-reform trend increases in both Level III/IV surgeries ( Conclusion: The integrated urban healthcare group model effectively strengthened primary care delivery in a resource-limited setting, achieving concurrent improvements in access, quality, and affordability. However, the gains in human resources were mainly immediate rather than sustained, suggesting that persistent workforce constraints can limit the translation of infrastructure expansion into long-term accessibility improvements. The experience of Dapeng, Shenzhen, China, offers valuable and transferable insights for health systems in comparable contexts seeking to implement integrated care reforms.