The Concept of Interoperability for AAL Systems

2.1 The General Definition

At the very top of an ‘interoperability scale’ are three levels, each one subdivided: functional, syntactic, and semantic. Full sharing of information requires that the two top levels of interoperability are reached: functional and syntactic interoperability: the ability of two or more systems to exchange information (so that it is human readable by the receiver); semantic interoperability: the ability for information shared by systems to be understood at the level of formally defined domain concepts (so that the information is computer processable by the receiving system).

To make interoperability clearly described, the terms of interfacing and integration have to be defined. The distinction between interfacing, integration and interoperability is extremely important.

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  Interface: a boundary at which interaction occurs between two systems, processes, etc. An interface defines how to access an object.

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  Integration: combination of diverse application entities into a relationship which functions as a whole

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  Interoperability: a state which exists between two application entities when, with regard to a specific task, one application entity can accept data from the other and perform that task in an appropriate and satisfactory manner without the need for extra operator intervention.

This definition of interoperability, in its mention of a specific task, usefully distinguishes interoperability from integration. It also brings precision and operational meaningfulness to the IEEE and ISO definition of interoperability namely

2.2 Interoperability in E-Health

The most known definitions of interoperability for healthcare systems are of three international organizations, CEN, IEE and HIMSS. These examine interoperability from different perspectives:

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  HIMSS describe the dimensions that comprise a more expansive notion of interoperability

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  CEN defines a broad array of user-driven interoperability functional profiles

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  IEEE analyses the modules of an interoperability’ s functional model

Studying these definitions, a common area of interoperability in e-Health is defined as presented in Table 1.