An example of a blood Rh antigen measurement.

{
  "resourceType" : "Observation",
  "id" : "rhstatus",
  "text" : {
    "status" : "generated",
    "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\"><p><b>Generated Narrative: Observation</b><a name=\"rhstatus\"> </a></p><div style=\"display: inline-block; background-color: #d9e0e7; padding: 6px; margin: 4px; border: 1px solid #8da1b4; border-radius: 5px; line-height: 60%\"><p style=\"margin-bottom: 0px\">Resource Observation &quot;rhstatus&quot; </p></div><p><b>status</b>: final</p><p><b>category</b>: Laboratory <span style=\"background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki\"> (<a href=\"http://terminology.hl7.org/5.4.0/CodeSystem-observation-category.html\">Observation Category Codes</a>#laboratory)</span></p><p><b>code</b>: Rh Type <span style=\"background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki\"> (<a href=\"https://loinc.org/\">LOINC</a>#88027-8 &quot;Rh group Ag [Type] on Red Blood Cells&quot;)</span></p><p><b>subject</b>: <a href=\"broken-link.html\">Patient/infant</a></p><p><b>effective</b>: 2018-03-11T16:07:54Z</p><p><b>value</b>: Rh(D) positive (finding) <span style=\"background: LightGoldenRodYellow; margin: 4px; border: 1px solid khaki\"> (<a href=\"https://browser.ihtsdotools.org/\">SNOMED CT</a>#165747007 &quot;Rh positive&quot;)</span></p></div>"
  },
  "status" : "final",
  "category" : [{
    "coding" : [{
      "system" : "http://terminology.hl7.org/CodeSystem/observation-category",
      "code" : "laboratory",
      "display" : "Laboratory"
    }],
    "text" : "Laboratory"
  }],
  "code" : {
    "coding" : [{
      "system" : "http://loinc.org",
      "code" : "88027-8",
      "display" : "Rh group Ag [Type] on Red Blood Cells"
    }],
    "text" : "Rh Type"
  },
  "subject" : {
    "reference" : "Patient/infant"
  },
  "effectiveDateTime" : "2018-03-11T16:07:54+00:00",
  "valueCodeableConcept" : {
    "coding" : [{
      "system" : "http://snomed.info/sct",
      "code" : "165747007",
      "display" : "Rh positive"
    }],
    "text" : "Rh(D) positive (finding)"
  }
}