{"abstract":false,"baseDefinition":"http://hl7.org/fhir/StructureDefinition/DataType","contact":[{"telecom":[{"system":"url","value":"http://hl7.org/fhir"}]},{"telecom":[{"system":"url","value":"http://www.hl7.org/Special/committees/fiwg"}]}],"date":"2026-03-29T21:54:20+00:00","derivation":"specialization","description":"Coding Type: A reference to a code defined by a terminology system.","differential":{"element":[{"comment":"Codes may be defined very casually in enumerations or code lists, up to very formal definitions such as SNOMED CT - see the HL7 v3 Core Principles for more information.","constraint":[{"expression":"code.exists().not() implies display.exists().not()","human":"A Coding SHOULD NOT have a display unless a code is also present. Computation on Coding.display alone is generally unsafe. 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\r\n\r\n\r\n\r\n\r\n\r\n
NameFlagsCard.TypeDescription & Constraints\"doco\"
\".\"\".\" CodingΣNElementA reference to a code defined by a terminology system
+ Warning: A Coding SHOULD NOT have a display unless a code is also present. Computation on Coding.display alone is generally unsafe. Consider using CodeableConcept.text

Elements defined in Ancestors: id, extension
\".\"\".\"\".\" systemΣ0..1uriIdentity of the terminology system
\".\"\".\"\".\" versionΣ0..1stringVersion of the system - if relevant
\".\"\".\"\".\" codeΣC0..1codeSymbol in syntax defined by the system
\".\"\".\"\".\" displayΣTC0..1stringRepresentation defined by the system
\".\"\".\"\".\" userSelectedΣ0..1booleanIf this coding was chosen directly by the user

\"doco\" Documentation for this format
","status":"generated"},"type":"Coding","url":"http://hl7.org/fhir/StructureDefinition/Coding","version":"6.0.0-ballot4"}