Observation

Search Observations

GET /Observation?patient={id}&category={cat}&code={code}&date={date}&_count={limit}&_offset={offset}

Parameters

Parameter	Type	Description
`patient`	string	Filter by patient resource_id
`category`	string	`vital-signs`, `laboratory`, `social-history`, `exam`
`code`	string	LOINC code (e.g., `8480-6` for systolic BP)
`date`	date	Filter by date

Create Observation

POST /Observation
Content-Type: application/json

Vital Signs Example

{
  "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",
        "display": "Blood pressure panel"
      }
    ]
  },
  "subject": { "reference": "Patient/ZCT_patient_001" },
  "effectiveDateTime": "2026-03-03T10:30:00Z",
  "component": [
    {
      "code": {
        "coding": [{ "system": "http://loinc.org", "code": "8480-6", "display": "Systolic" }]
      },
      "valueQuantity": { "value": 120, "unit": "mmHg" }
    },
    {
      "code": {
        "coding": [{ "system": "http://loinc.org", "code": "8462-4", "display": "Diastolic" }]
      },
      "valueQuantity": { "value": 80, "unit": "mmHg" }
    }
  ]
}

ObservationDefinition

Define templates for observation types:

GET /ObservationDefinition?code={code}
POST /ObservationDefinition
PUT /ObservationDefinition/{resource_id}
DELETE /ObservationDefinition/{resource_id}

Read / Update / Delete

GET /Observation/{resource_id}
PUT /Observation/{resource_id}
DELETE /Observation/{resource_id}