http://hl7.org/fhir/StructureDefinition/questionnaire-baseType|5.2.0

This identifies the underlying type in a profile, when a questionnaire is generated from a profile.

element_id	types
Extension
Extension.extension
Extension.url
Extension.value[x]	code
Extension
Extension.id	http://hl7.org/fhirpath/System.String
Extension.extension	Extension
Extension.url	http://hl7.org/fhirpath/System.String
Extension.value[x]	code