NameFlagsCard.TypeDescription & Constraintsdoco
.. Observation 0..* Observation Measurements and simple assertions
... subject Σ 1..1 Reference(RareLink IPS Patient) Who and/or what the observation is about
.... reference ΣC 0..1 string Literal reference, Relative, internal or absolute URL
.... identifier Σ 0..1 Identifier Logical reference, when literal reference is not known

doco Documentation for this format