RelatedPerson — Patient relative

Spouse, parent, caregiver, legal representative: a person linked to the patient who can make decisions, be contacted, but is not themselves treated.

Purpose

RelatedPerson models a person linked to a patient: typically an emergency contact, a parent consenting for a minor, a legal guardian consenting for a protected adult, a family caregiver attending appointments. RelatedPerson is the FHIR equivalent of the HL7 v2 NK1 segment.

Key fields

JSON example

Spouse as emergency contact, FR preferred language:

{
  "resourceType": "RelatedPerson",
  "id": "spouse-doe-jane",
  "identifier": [{
    "system": "urn:oid:1.2.34",
    "value": "RP-2026-001"
  }],
  "active": true,
  "patient": { "reference": "Patient/doe-john" },
  "relationship": [{
    "coding": [{
      "system": "http://terminology.hl7.org/CodeSystem/v3-RoleCode",
      "code": "SPS",
      "display": "spouse"
    }]
  }, {
    "coding": [{
      "system": "http://terminology.hl7.org/CodeSystem/v2-0131",
      "code": "C",
      "display": "Emergency Contact"
    }]
  }],
  "name": [{
    "use": "official",
    "family": "Doe",
    "given": ["Jane"]
  }],
  "telecom": [{
    "system": "phone",
    "value": "+33 6 12 34 56 78",
    "use": "mobile",
    "rank": 1
  }, {
    "system": "email",
    "value": "jane.doe@example.org",
    "rank": 2
  }],
  "gender": "female",
  "birthDate": "1976-03-22",
  "address": [{
    "use": "home",
    "line": ["12 rue de la République"],
    "city": "Lyon",
    "postalCode": "69001",
    "country": "FR"
  }],
  "communication": [{
    "language": {
      "coding": [{
        "system": "urn:ietf:bcp:47",
        "code": "fr-FR"
      }]
    },
    "preferred": true
  }]
}

Common pitfalls

• Confusing with Patient — a RelatedPerson is not treated. If they become a patient themselves (e.g. hospitalization), create a separate Patient linked via Person.
• No relationship — an untyped relationship is unusable: how to know if it's the guardian or just a friend?
• Medical data on RelatedPerson — anti-pattern, no Observation/Condition tied to a RelatedPerson. Use FamilyMemberHistory.
• Multiple code systems mixed — relationship accepts v3-RoleCode AND v2-0131: document the code system per entry.
• Forgotten period — an ex-spouse stays linked without period.end: confusion source.

Related resources

• Patient — linked patient.
• Person — cross-resource identity merge.
• FamilyMemberHistory — history.
• Consent — consent via legal representative.
• Practitioner — if the relative is also a provider (rare but possible).