This is represented as nullFlavor="UNK" in HL7 documents
0‑L
1
Mann
2.16.578.1.12.4.1.1.3101
0‑L
2
Kvinne
2.16.578.1.12.4.1.1.3101
0‑L
9
Ikke spesifisert
2.16.578.1.12.4.1.1.3101
Legenda: Type L=leaf, S=specializable, A=abstract, D=deprecated. NullFlavor OTH (other) suggests text in originalText. HL7 V3: NullFlavors to appear in @nullFlavor attribute instead of @code.