Methodology of integration of a clinical data warehouse with a clinical information system: the HEGP case

Clinical Data Warehouses (CDW) can complement current Clinical Information Systems (CIS) with functions that are not easily implemented by traditional operational database systems. Here, we describe the design and deployment strategy used at the Pompidou University Hospital in southwest Paris. Four realms are described: technological realm, data realm, restitution realm, and administration realm. The corresponding UML use cases and the mapping rules from the shared integrated electronic health records to the five axes of the i2b2 CDW star model are presented. Priority is given to the anonymization and security principles used for the 1.2 million patient records currently stored in the CDW. Exploitation of a CDW by clinicians and investigators can facilitate clinical research, quality evaluations and outcome studies. These indirect benefits are among the reasons for the continuous use of an integrated CIS.