  Legacy Electronic Health Records (EHRs) systems were not developed with the
level of connectivity expected from them nowadays. Therefore, interoperability
weakness inherent in the legacy systems can result in poor patient care and
waste of financial resources. Large hospitals are less likely to share their
data with external hospitals due to economic and political reasons. Motivated
by these facts, we aim to provide a set of software implementation guidelines,
i.e., MedShare to deal with interoperability issues among disconnected
healthcare systems. The proposed integrated architecture includes: 1) a data
extractor to fetch legacy medical data from a hemodialysis center, 2)
converting it to a common data model, 3) indexing patient information using the
HashMap technique, and 4) a set of services and tools that can be installed as
a coherent environment on top of stand-alone EHRs systems. Our work enabled
three cooperating but autonomous hospitals to mutually exchange medical data
and helped them develop a common reference architecture. It lets stakeholders
retain control over their patient data, winning the trust and confidence much
needed towards a successful deployment of MedShare. Security concerns were
effectively addressed that also included patient consent in the data exchange
process. Thereby, the implemented toolset offered a collaborative environment
to share EHRs by the healthcare providers.
