How

Assign the Observation resource a logical id.
Reference the logical ID of a previously created Patient resource in the subject field of the Observation.
Status must be included. See the FHIR R4 spec for the status value set.
Category must be included and should use the “DIARYENTRY” code with the PKB system of: "http://fhir.patientsknowbest.com/codesystem/observation-category ".
Code should be the journal entry’s “subject” or title of the entry.
The journal entry’s main content should be sent in Observation.value.
Observation.effectiveDateTime should be used as the date of the journal entry.
Use an extension to reference an attached document.
POST https://{client}.fhir-api.sandbox.patientsknowbest.com/fhir/Observation

Journal Entry Example

{
  "resourceType": "Observation",
  "status": "final",
  "category": [
    {
      "coding": [
        {
          "system": "http://fhir.patientsknowbest.com/codesystem/observation-category",
          "code": "DIARYENTRY",
          "display": "Journal Entry"
        }
      ]
    }
  ],
  "code": {
    "text": "Rash appears"
  },
  "subject": {
    "reference": "Patient/4aaa8eac-ee90-20ab-27ba-a94bb9b7eef5"
  },
  "effectiveDateTime": "2025-10-27T09:47:00+00:00",
  "valueString": "A rash appears on my forearm after taking the medicine."
  }

Creating Journal Entries

How

Journal Entry Example