CodeSystems
CodeSystems define a set of codes with meanings (also known as enumeration, terminology, classification, and/or ontology)
The CodeSystem resource is used to declare the existence of a code system, and its key properties:
- Identifying URL and version.
- Description, Copyright, publication date, and other metadata.
- Some key properties of the code system itself - whether it's case sensitive, version safe, and whether it defines a compositional grammar.
- What filters can be used in value sets that use the code system in a ValueSet.compose element.
- What properties the concepts defined by the code system.
CodeSystems are used in ValueSet resources. In resources (Patient, Device, Observation, etc...), the Coding data type refers to CodeSystem resources by their canonical url.
Below, there is an index of the used CodeSystems in this Data Model.