Layered implementation view of a SOA based electronic health record

Abstract

Interoperability between legacy systems has crucial importance for integration of many distributed systems. Within health information systems, the need for interop- erability between legacy systems is well-known, as these are heterogeneous systems which have a long lifespan. An interesting example of health information systems is the Electronic Health Record (EHR), a virtual record of every health-related event, including hospital admission, general practitioner visit, exams, and allergies experienced by individuals over their lifespan from in uterus to death. A great challenge for implementing EHR applications is that these systems often have to integrate large amount of data gathered from legacy systems into a single application. This paper describes in detail the implementation view of a software architecture based on web services for developing an EHR application in a public hospital. The architecture has been defined with a layered style for implementation and on services identified within current legacy systems. Detailed explanation on the software development, in- cluding architectural elements and services catalog are described as well.