What is an Archetype?
The Concise Oxford Dictionary defines an archetype as "an original model, prototype or typical specimen". In openEHR, an archetype is the model (or pattern) for the capture of clinical information - a machine readable specification of how to store patient data using the openEHR Reference Model.
Archetypes are a keystone of the openEHR architecture. Each archetype describes a complete clinical knowledge concept such as 'diagnosis' or 'test result'. By design, they provide structure and specify content which means that archetypes can be both clinically meaningful and interpretable by EHR systems. Archetyped data will have the same meaning no matter what context it is used within the EHR and, similarly, no matter which EHR system it is used or what language is used.
Classes
COMPOSITION Class
A COMPOSITION is a container class in the openEHR reference model - it is the unit of committal to the EHR. That is to say, all information within the EHR is contained within a Composition. Any Composition, once committed, is retained as part of the EHR - if it is edited or changed in any way then the changes are committed as a new version of the Composition. Further, all information transferred from one EHR to another is transferred as Compositions.
Compositions contain SECTIONs - or organising classes, which themselves contain ENTRYs.
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