• Include these codes as defined in http://terminology.hl7.org/CodeSystem/v3-ActReason
    CodeDisplayDefinition
    RETretest**Definition:**The event occurred so that a test or observation performed at a prior event could be performed again due to conditions set forth in the protocol.
    SCHscheduled**Definition:**The event occurred due to it being scheduled in the research protocol.
    TRMtermination**Definition:**The event occurred in order to terminate the subject's participation in the study.
    UNSunscheduled**Definition:**The event that occurred was initiated by a study participant (e.g. the subject or the investigator), and did not occur for protocol reasons.
 <status value="active"/> <experimental value="false"/> <date value="2014-03-26"/> <description value="**Definition:**Specifies the reason that an event occurred in a clinical research study."/> <compose> <include> <system value="http://terminology.hl7.org/CodeSystem/v3-ActReason"/> <concept> <code value="RET"/> </concept> <concept> <code value="SCH"/> </concept> <concept> <code value="TRM"/> </concept> <concept> <code value="UNS"/> </concept> </include> </compose> </ValueSet>