codesystems
An optional clause in a valueset definition that restricts value set membership to codes from a specific set of code systems. When present, only codes from the listed code systems are considered in scope.
Examples
Restrict value set to a single code system
valueset "Diabetes": 'http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113883.3.464.1003.103.12.1001'
codesystems { "SNOMED-CT" }Restrict value set to multiple code systems
valueset "Inpatient Encounter": 'http://cts.nlm.nih.gov/fhir/ValueSet/2.16.840.1.113883.3.666.5.307'
codesystems { "SNOMED-CT", "ICD-10-CM" }EBNF
codesystems
: 'codesystems' '{' codesystemIdentifier (',' codesystemIdentifier)* '}'
;