fhir-data-model-design

Maps clinical data types to specific FHIR R4 resources, terminology bindings, and relationships. Unlike most other skills, this one is expert-driven — it provides recommendations rather than asking Socratic questions.

What It Produces

For each FHIR resource used:

• Profile (base FHIR or specific IG profile URL)
• Clinical use description
• Key fields with types and value set bindings
• Terminology bindings (LOINC, SNOMED CT, RxNorm, ICD-10-CM)
• Sample FHIR JSON with realistic values

Plus:

• Terminology bindings table
• Resource relationships
• FHIR REST API patterns (read, search, write, transaction bundles)
• Data flow descriptions
• Implementation notes and known gaps

Output

Produces docs/planning/fhir-data-model.md.

Example

AI:   What clinical data does your app track? List every type —
      vitals, labs, questionnaires, medications, conditions.

You:  Blood pressure, heart rate, daily step count, and a
      weekly PHQ-9 depression screening.

AI:   Based on that, here's the FHIR resource mapping:

      Blood pressure → Observation (US Core Blood Pressure profile)
        LOINC: 85354-9, components: systolic 8480-6, diastolic 8462-4

      Heart rate → Observation (US Core Heart Rate profile)
        LOINC: 8867-4

      Step count → Observation
        LOINC: 55423-8

      PHQ-9 → QuestionnaireResponse + Observation (score)
        Questionnaire canonical: http://loinc.org/q/44249-1
        Score LOINC: 44261-6

      Sample FHIR JSON for a blood pressure reading:
      {
        "resourceType": "Observation",
        "status": "final",
        "category": [{"coding": [{"system": "http://terminology.hl7.org/CodeSystem/observation-category", "code": "vital-signs"}]}],
        "code": {"coding": [{"system": "http://loinc.org", "code": "85354-9"}]},
        "component": [
          {"code": {"coding": [{"system": "http://loinc.org", "code": "8480-6"}]}, "valueQuantity": {"value": 120, "unit": "mmHg"}},
          {"code": {"coding": [{"system": "http://loinc.org", "code": "8462-4"}]}, "valueQuantity": {"value": 80, "unit": "mmHg"}}
        ]
      }

Limitations

• Assumes FHIR R4; older versions not addressed
• Does not resolve individual terminology codes (provides system URIs; you look up specific codes)
• Does not provide clinical validation of terminology — flags where clinical review is needed
• Does not address storage layer details (database choice, indexing)
• Does not implement backend API code — provides the specification