http://hl7.org/fhir/StructureDefinition/cqf-cqlAccessModifier|5.2.0

Indicates the access modifier (i.e. public or private) of a CQL declaration. When CQL library declarations are represented in FHIR structures such as ParameterDefinition, this extension represents the access modifier of the declaration.
element_idtypes
Extension
Extension.url
Extension.value[x]
Extension
Extension.id
Extension.extension
Extension.url
Extension.value[x]