As Information Communication Technologies (ICTs) are growing, there have been ceaseless efforts to develop a National Health Information Infrastructure (NHII). One of the challenges in constructing a NHII is concerned with the management of Electronic Health Records (EHRs). In particular, exchanging EHRs is an important factor in establishing interoperability within a NHII, and the reusability of the functionality for exchanging EHRs is one of major solutions to construct an NHII. In this study, we obtain several component models, and conduct empirical studies to validate the component models in terms of component reusability. Using HL7 CDA (Health Level 7 Clinical Document Architecture) as an EHR standard, we implemented three prototypes of the EHR Exchanger based on JavaBeans, the exogenous connectors and the mediator connector respectively. As shown in the experiment results, the reuse approach using a mediator connector leads to better component reusability in terms of external dependency, total coupling between objects (CBO), additional lines of codes (LOC), and performance. Thus, we believe that the reuse approach using a mediator connector yields many benefits in terms of component reusability for the EHR Exchanger implementation.