This is the Continuous Integration Build of FHIR (will be incorrect/inconsistent at times). 
See the Directory of published versions
Clinical Trial Enrollment
{
  "resourceType" : "Flag",
  "id" : "clinical-trial-enrollment",
  "text" : {
    "status" : "generated",
    "div" : "<div xmlns=\"http://www.w3.org/1999/xhtml\">Patients in Group 102 are enrolled in the XYZ123 Clinical Trial.</div>"
  },
  "identifier" : [{
    "value" : "clinical-trial-2024-group-a"
  }],
  "status" : "active",
  "category" : [{
    "coding" : [{
      "system" : "http://terminology.hl7.org/CodeSystem/flag-category",
      "code" : "research",
      "display" : "Research"
    }],
    "text" : "Research"
  }],
  "code" : {
    "coding" : [{
      "system" : "http://example.org/local",
      "code" : "clinical-trial",
      "display" : "Clinical Trial Enrollment"
    }],
    "text" : "Patients are enrolled in the XYZ123 Clinical Trial."
  },
  "subject" : {
    "reference" : "Group/102",
    "display" : "Group 102"
  },
  "period" : {
    "start" : "2024-01-01"
  },
  "author" : {
    "display" : "ABC Research Institute"
  }
}
 
Usage note: every effort has been made to ensure that the
examples are correct and useful, but they are not a normative part 
of the specification.