Use Case(s) 

To express presence or absence of a clinical oservationclinical phenomenon

Artifact

Presence Absence reference set

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This reference set is for recording and retrieving presence-absence information. In practice, the presence or absence of a phenomenon /finding/observation will be coordinated or constructed using members of this refset to convey the 'absent-ness' or present-ness' of something a clinician wishes to record.

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