A Service-Oriented, API-Driven Framework for Interoperability of Health Information Systems in the Democratic Republic of Congo

Interoperability among health information systems remains a major challenge in the Democratic Republic of Congo (DRC) due to fragmented infrastructures, heterogeneous software platforms, limited connectivity, and lack of standardized data exchange mechanisms. These challenges hinder effective data sharing between hospitals, laboratories, and national health systems, ultimately affecting healthcare delivery and public health decision-making. This paper proposes an API-driven interoperability framework based on Service-Oriented Architecture (SOA) and the Service-Oriented Analysis and Design (SOAD) methodology to address these issues. The proposed approach follows a structured methodology organized into three abstraction levels: Conceptual View (CV), Logical View (LV), and Physical View (PV). At the conceptual level, healthcare business processes are analyzed and decomposed into reusable business services, consolidated into a service portfolio. At the logical level, Enterprise Architecture and SOA principles are applied to map business services into interoperable software services exposed through RESTful APIs. At the physical level, the solution is implemented using a layered and microservices-based architecture, incorporating an API Gateway, domain-specific microservices, MySQL and MongoDB for transactional data storage, and Hadoop for large-scale health data analytics. The architecture is designed to operate under the infrastructural constraints of the DRC by supporting modular deployment, loose coupling, and resilience to network instability. Scenario-based evaluation demonstrates that the proposed solution enables secure, scalable, and flexible data exchange without requiring major modifications to existing systems. The results indicate that an SOAD-guided, API-driven interoperability framework is a viable and sustainable approach for strengthening digital health ecosystems in low-resource environments such as the DRC.