NCPI FHIR Implementation Guide v2
0.2.0 - ci-build

NCPI FHIR Implementation Guide v2 - Local Development build (v0.2.0) built by the FHIR (HL7® FHIR® Standard) Build Tools. See the Directory of published versions

ValueSet: Biological Relationship Codes

Official URL: https://nih-ncpi.github.io/ncpi-fhir-ig-2/ValueSet/family-biological-relationship-vs Version: 0.2.0
Draft as of 2025-12-03 Computable Name: FamilyBiologicalRelationshipVS

List of codes indicating the biological relationship between two individuals in a family. It is restrictive to encourage a standardized representation.

Code Selection Rationale

Parent Codes

We use the NCI Thesaurus here for the mother and father because its definitions are more precise.

In contrast, the parental family-role's codes are less refined:

In particular, "Biological Mother" excludes surrogates but NMTH is ambiguous. "Biological Father" specifies fertilization of an ovum by sperm, whereas NFTH uses the ambiguous term "begets," which could include other mechanisms.

Twin Codes

For twins, we use the RoleCode ITWIN code rather than the NCI C73429.

Though being "offspring" of the same fertilized egg is questionable wording, we use ITWIN because it also allows other multiples (triplets, quadruplets, etc.) to be represented with the same code whereas C73429 is only for twins.

Note for upgrading to FHIR R5

When we add support for R5 to the IG, we should add the rest of the codes from http://terminology.hl7.org/ValueSet/v3-FamilyMember as additional bindings to guide users when not using one of the main bindings.

We intend that when users need to use a code that is not in the main bindings, they should default to the FamilyMember ValueSet. However, in R4, there is no way to express this in the ValueSet itself.

References

Logical Definition (CLD)

This value set includes codes based on the following rules:

 

Expansion

No Expansion for this valueset (not supported by Publication Tooling)


Explanation of the columns that may appear on this page:

Level A few code lists that FHIR defines are hierarchical - each code is assigned a level. In this scheme, some codes are under other codes, and imply that the code they are under also applies
System The source of the definition of the code (when the value set draws in codes defined elsewhere)
Code The code (used as the code in the resource instance)
Display The display (used in the display element of a Coding). If there is no display, implementers should not simply display the code, but map the concept into their application
Definition An explanation of the meaning of the concept
Comments Additional notes about how to use the code