Specification

This page outlines how Rad AI profiles the FHIR R4 Observation resource. Use the Field Descriptions and Cardinality table below to identify required and optional elements for integration with the Rad AI reporting application.

Example Resource

{
  "resourceType": "Observation",
  "status": "final",
  "issued": "2020-09-07T15:02:03.651Z",
  "subject": {
    "type": "Patient",
    "identifier": {
      "system": "http://example.org/patient-id",
      "value": "1234",
      "type": {
        "coding": [
          {
            "system": "http://terminology.hl7.org/CodeSystem/v2-0203",
            "code": "MR"
          }
        ]
      }
    }
  },
  "partOf": [
    {
      "type": "ImagingStudy",
      "identifier": {
        "system": "http://example.org/filler-order-number",
        "value": "1234",
        "type": {
          "coding": [
            {
              "system": "http://terminology.hl7.org/CodeSystem/v2-0203",
              "code": "ACSN"
            }
          ]
        }
      }
    },
    {
      "type": "ImagingStudy",
      "identifier": {
        "system": "urn:dicom:uid",
        "value": "urn:oid:2.16.124.113543.1154777499.30246.19789.3503430046"
      }
    }
  ],
  "code": {
    "coding": [
      {
        "system": "http://loinc.org",
        "code": "10231-9",
        "display": "Right ventricular Ejection fraction"
      }
    ]
  },
  "valueQuantity": {
    "value": 29,
    "unit": "%",
    "system": "http://unitsofmeasure.org",
    "code": "%"
  },
  "basedOn": [
    {
      "type": "ServiceRequest",
      "identifier": {
        "system": "http://example.org/placer-order-number",
        "value": "1234"
      }
    }
  ],
  "referenceRange": [
    {
      "low": {
        "value": 50,
        "unit": "%",
        "system": "http://unitsofmeasure.org",
        "code": "%"
      },
      "high": {
        "value": 70,
        "unit": "mmol/l",
        "system": "http://unitsofmeasure.org",
        "code": "%"
      }
    }
  ],
  "interpretation": [
    {
      "coding": [
        {
          "system": "http://terminology.hl7.org/CodeSystem/v3-ObservationInterpretation",
          "code": "LU",
          "display": "Significantly low"
        }
      ]
    }
  ],
  "text": {
    "status": "generated",
    "div": "<div xmlns=\"http://www.w3.org/1999/xhtml\">29%</div>"
  }
}

Field descriptions and cardinality

Field	Description	Required	Example Value
resourceType	The type of the resource	Yes	Observation
status	The status of the observation	Yes	final
issued	The time the observation was issued	Yes	2020-09-07T15:02:03.651Z
meta.account.reference	The Rad AI-defined FHIR Organization ID for the customer	Yes	Organization/00000000-0000-0000-0000-000000000000
subject.type	The type of subject	Yes	Patient
subject.identifier	Identifier details for the subject (patient)	Yes
system	Optional system for patient IDs (Assigning Authority)	No	http://example.org/patient-ids
value	The patient identifier value	Yes	1234
type	The type of identifier	Yes
coding	Coding details for identifier type	Yes
system	The coding system for identifier type	Yes	http://terminology.hl7.org/CodeSystem/v2-0203
code	The code representing the identifier type	Yes	MR
partOf	List of references to related ImagingStudy resources	Yes
type	The type of related resource	Yes	ImagingStudy
identifier	Identifier details for the ImagingStudy	Yes
system	Optional system for the filler order number	No	http://example.org/filler-order-number
value	The value of the filler order number	Yes	1234
type	The type of identifier	Yes
coding	Coding details for identifier type	Yes
system	The coding system for identifier type	Yes	http://terminology.hl7.org/CodeSystem/v2-0203
code	The code representing the identifier type	Yes	ACSN
partOf (StudyUID)	Optional StudyUID details	No
system	The system for the StudyUID	No	urn:dicom:uid
value	The value of the StudyUID	No	urn:oid:2.16.124.113543.1154777499.30246.19789.3503430046
code	The code representing the observation	Yes
coding	Coding details for the observation code	Yes
system	The coding system for the observation code	Yes	http://loinc.org
code	The code representing the observation	Yes	10231-9
display	Optional public display name for the observation	No	Right ventricular Ejection fraction
valueQuantity	The quantity value of the observation	Yes
value	The numeric value of the observation	Yes	29
unit	The unit of measurement	Yes	%
system	The system for units of measurement	Yes	http://unitsofmeasure.org
code	The code representing the unit	Yes	%
basedOn	Link to the ServiceRequest (Placer Order Number)	Yes
type	The type of related resource	Yes	ServiceRequest
identifier	Identifier details for the ServiceRequest	Yes
system	Optional system for the placer order number	No	http://example.org/placer-order-number
value	The value of the placer order number	Yes	1234
referenceRange	Optional reference range details for the observation	No
low.value	The low-end value of the reference range	No	50
low.unit	The unit of measurement for the low-end value	No	%
high.value	The high-end value of the reference range	No	70
high.unit	The unit of measurement for the high-end value	No	mmol/l
interpretation	Optional interpretation of the observation	No
coding	Coding details for interpretation	No
system	The system for interpretation codes	Yes	http://terminology.hl7.org/CodeSystem/v3-ObservationInterpretation
code	The code representing the interpretation	Yes	LU
display	The display text for the interpretation	No	Significantly low
text	Narrative text of the observation	No
status	The status of the narrative text	No	generated
div	The narrative text in XHTML format	Yes	<div xmlns="http://www.w3.org/1999/xhtml">29%</div>