[The principle target that the service acts on. E.g. the patient in physical examination, a specimen in a lab observation. May also be a patient's family member (teaching) or a device or room (cleaning, disinfecting, housekeeping). Note: not all direct targets are subjects, consumables, and devices used as tools for a service are not subjects. However, a device may be a subject of a maintenance service. ( HL7V3.0 )]
UMLS (HL7) C1550501 Relation/PAR: direct target
Relation/CHD: specimen