Person — Cross-resource master identity

The physician who is also a patient at the hospital where they practice: two resources (Practitioner + Patient) but a single physical person. Person materializes that equivalence.

Purpose

A physical person can have several roles in the system: physician (Practitioner), patient (Patient), companion for a relative (RelatedPerson), admin staff member (Person alone). Person ties these roles via link[], with an assurance level on each link: level1 (declarative) to level4 (strong identity verification).

Key fields

JSON example

Person linking Patient + Practitioner + RelatedPerson:

{
  "resourceType": "Person",
  "id": "person-doe-john",
  "identifier": [{
    "system": "http://example.org/persons",
    "value": "PER-2026-00042",
    "use": "usual"
  }, {
    "system": "urn:oid:1.2.250.1.213.1.4.8",
    "value": "199004587890190",
    "use": "official",
    "type": {
      "coding": [{
        "system": "http://terminology.hl7.org/CodeSystem/v2-0203",
        "code": "NI",
        "display": "National identifier"
      }]
    }
  }],
  "name": [{
    "use": "official",
    "family": "Doe",
    "given": ["John", "Alexander"]
  }],
  "telecom": [{
    "system": "email",
    "value": "j.doe@example.org"
  }],
  "gender": "male",
  "birthDate": "1972-05-15",
  "active": true,
  "link": [{
    "target": { "reference": "Patient/doe-john" },
    "assurance": "level3"
  }, {
    "target": { "reference": "Practitioner/prac-doe-john" },
    "assurance": "level3"
  }, {
    "target": { "reference": "RelatedPerson/parent-doe-jr" },
    "assurance": "level2"
  }]
}

Common pitfalls

• Person used as Patient — Person has no Encounter, Condition, etc. It is an identity node, not a patient.
• No Master Person Index — without a dedicated MPI, Person is overhead; on a single EHR, Patient.link suffices for merging.
• Links without assurance — a level-1 link (declarative) and a level-4 link (verified papers) don't carry the same legal weight.
• Confusing Person active with linked Patient/Practitioner — each resource has its own lifecycle.
• Cyclic links — a Person pointing to another Person must avoid cycles (A → B → A).

Related resources

• Patient — one role.
• Practitioner — another role.
• RelatedPerson — yet another role.
• Person.link — MPI chaining.