Unintended consequences of the physical and health integration policy in China's primary healthcare: a grounded theory study of policy implementation dynamics.

Introduction: Under the framework of the "Healthy China" initiative, the Physical and Health Integration (PHI) policy has become a strategic tool to promote health-oriented transitions in primary healthcare. While existing research has largely focused on policy design and expected outcomes, limited attention has been devoted to the actual implementation processes and unintended consequences at the frontline. This study addresses this gap by examining how frontline practitioners enact, adapt, and reinterpret the PHI policy in practice. Methods: This study employs grounded theory to explore the dynamic mechanisms shaping PHI policy implementation. Drawing on 20 in-depth interviews with primary healthcare practitioners across China, unintended consequences were identified through open, axial, and selective coding. The analytical process enabled the extraction of recurrent patterns and the development of a mechanism-based explanatory model. Results: The analysis reveals a non-linear, chain-like implementation process characterized by cognitive misalignment, resource and institutional constraints, and diversified behavioral strategies among frontline actors. Unintended consequences emerged through symbolic compliance, resource distortion, and behavioral adaptation. Frontline practitioners adopted varied strategies-from passive compliance and symbolic fulfillment to localized adaptation-resulting in fragmented implementation. These interacting mechanisms formed a self-reinforcing cycle that reproduced gaps between policy intentions and practice. Discussion: The findings align with broader policy implementation theories. Symbolic compliance reflects Lipsky's Street-Level Bureaucracy perspective, wherein frontline actors adapt or distort directives to accommodate local constraints. Similarly, Pressman and Wildavsky's Implementation Gap framework helps explain how limited resources and ambiguous guidance contribute to deviations between intended and actual policy outcomes. Based on these insights, the study proposes a "mechanism model of unintended consequences" that highlights structural challenges related to intersectoral coordination, knowledge translation, and performance incentives. The study contributes to public policy implementation research by offering a micro-level explanation of how ambitious health reforms are translated, negotiated, and reframed in grassroots contexts.