Virtual objects in large scale health information systems

This paper presents an approach of data integration in Health Virtual Organization (HVO). It targets large scale contexts where high distribution and autonomy of sources produce complex integration scenarios. The principle is to provide a high conceptual level composed of Virtual Data Objects (VDO) that can be queried independently of the data sources that are behind them and without requiring technical skills. The approach uses a mediation architecture improved to be viable in large scale contexts through the concept of query cartography and applying a semantic caching strategy specific for VDOs that reduces network latency.