This page is part of the MII Implementation Guide Core Dataset Base (v2027.0.0-ballot: 2027 Ballot 1) based on FHIR (HL7® FHIR® Standard) R4. This is the current published version in its permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions
This page provides UML class diagrams for the logical models of the MII core dataset base modules. These diagrams illustrate the relationships between the different data elements and classes.
Person Module
The following diagram shows the logical structure of the Person module:
Treatment Case Module
The following diagram shows the logical structure of the Treatment Case module:
Assignment of Care Units to Departments
The UML model distinguishes the static organizational assignment of care units from the hierarchy of individual encounters. The model allows care units to be assigned directly to a facility and represented without an additional department assignment. Care units may additionally be assigned to one or more departments. This supports centrally operated, temporary, or cross-departmental care units that do not have a single department assignment. A missing department assignment therefore does not imply that the care unit has no organizational owner; its association with the facility remains present.
The relationship between care units and departments is modeled as a regular many-to-many association rather than a composition because the same care unit can be shared by multiple departments. The relationship between facilities and departments is likewise modeled as a regular association: the UML diagram expresses organizational assignments, not shared lifecycles of the objects. This static assignment must not be interpreted as multiple Encounter.partOf references: in FHIR R4, an individual encounter can reference at most one parent encounter using Encounter.partOf. The same care unit can nevertheless be used as the location of different encounters, each in the context of its applicable department contact.
Recommended Relationship Between Department Contacts and Diagnoses
The Treatment Case UML diagram shows the department contact assigning a specific role to a diagnosis. The department contact represents the contact level currently recommended by the implementation guide. This is SHOULD-level guidance; other contact levels remain possible depending on the use case.
Diagnosis Module
The following diagram shows the logical structure of the Diagnosis module:
The Diagnosis UML diagram shows the department contact as the general contact context of a diagnosis. The department contact represents the contact level currently recommended by the implementation guide. This is SHOULD-level guidance; other contact levels remain possible depending on the use case.
Procedure Module
The following diagram shows the logical structure of the Procedure module:
The Procedure UML diagram shows the department contact as the general contact context of a procedure and thereby represents the implementation currently recommended by the implementation guide. Other contact levels remain possible depending on the use case.
