Figure 6

Simplified example of the ArchiMed data model in UML format. In the ArchiMed system an EHR consists of a set of DOCUMENTs, which themselves hold data VALUEs. The possible DOCUMENT structures are determined by the FORM package within the data model. One instance of the FORM class describes the structure of a class of DOCUMENTs. Each time a FORM is populated with data for a particular patient, the patient data are stored in a new DOCUMENT for this particular FORM. A FORM consists of one or more PAGEs. PAGEs may contain other PAGEs, TEXT_OBJECTs (e.g., fixed text, lines, boxes), or ENTRY_FIELDs. Each ENTRY_FIELD refers to a VARIABLE (e.g., systolic blood-pressure), and holds an actual data VALUE. VARIABLEs may be reused by different ENTRY_FIELDs. For VALUEs only primitive data types are supported. If multiple VALUEs need to be collectable for an ENTRY_FIELD, the latter may be embedded in a TABLE. A TABLE may also nest a group of logically related ENTRY_FIELDs.