NameFlagsCard.TypeDescription & Constraintsdoco
.. Extension 0..* Extension Age at Onset
ele-1: All FHIR elements must have a @value or children
ext-1: Must have either extensions or value[x], not both
... extension 0..0
... url 1..1 uri "https://github.com/BIH-CEI/RareLink/StructureDefinition/age-at-onset"
... value[x] 0..1 CodeableConcept Value of extension
Binding: Age at Onset Value Set (extensible)
ele-1: All FHIR elements must have a @value or children

doco Documentation for this format