Multilevel Implementation Architecture (MIA) in Health Systems: From Fragmentation to Functional Coherence

Background Fragmentation continues to constrain the effectiveness of health system reforms, particularly where expanded policy frameworks and coverage have not translated into consistent implementation. While implementation science has advanced the identification of barriers and facilitators—most notably through frameworks such as the Consolidated Framework for Implementation Research (CFIR)—less attention has been given to how structural misalignment across system levels generates recurrent implementation gaps. Methods This study develops the Multilevel Implementation Architecture (MIA) through a problem-driven conceptual analysis, integrating literature on health systems governance, implementation science, and complex adaptive systems. The framework is informed by established theories, including CFIR and street-level bureaucracy, and incorporates comparative system configurations as analytical reference points. Results The MIA conceptualizes implementation as an emergent property of alignment across governance, institutional, operational, and territorial levels. It explicitly incorporates a human layer as a central mechanism of adaptive mediation, explaining how actors sustain coherence in fragmented contexts. To support analytical application, the framework proposes two operational indicators: the Structural Fidelity Index (SFI), which assesses the congruence between institutional design and observed practice, and the Evidence-Based Adaptation Index (EBAI), which captures the system’s capacity to adjust implementation based on territorial feedback. Values of SFI greater than one may indicate institutional dissonance, where performance is sustained through compensatory human effort rather than structural coherence. Conclusion The MIA provides a system-level perspective on implementation, complementing intervention-focused approaches. By conceptualizing coherence as a measurable property, it offers a foundation for strengthening alignment across system levels and informing policy strategies aimed at improving implementation performance in fragmented settings.