<?xml version="1.0" encoding="UTF-8"?><CodeSystem xmlns="http://hl7.org/fhir"><id value="evidence-variable-event"/><meta><lastUpdated value="2026-04-01T17:59:15.240+00:00"/></meta><text><status value="generated"/><div xmlns="http://www.w3.org/1999/xhtml"><p class="res-header-id"><b>Generated Narrative: CodeSystem evidence-variable-event</b></p><a name="evidence-variable-event"> </a><a name="hcevidence-variable-event"> </a><p>This case-sensitive code system <code>http://hl7.org/fhir/evidence-variable-event</code> defines the following codes:</p><table class="codes"><tr><td style="white-space:nowrap"><b>Code</b></td><td><b>Display</b></td><td><b>Definition</b></td></tr><tr><td style="white-space:nowrap">study-start<a name="evidence-variable-event-study-start"> </a></td><td>Study Start</td><td>The time of enrollment for the study participant</td></tr><tr><td style="white-space:nowrap">treatment-start<a name="evidence-variable-event-treatment-start"> </a></td><td>Start of Treatment</td><td>The time of initiation of the treatment</td></tr><tr><td style="white-space:nowrap">condition-detection<a name="evidence-variable-event-condition-detection"> </a></td><td>Detection of Condition</td><td>The time of first detection of the condition</td></tr><tr><td style="white-space:nowrap">condition-treatment<a name="evidence-variable-event-condition-treatment"> </a></td><td>Treatment of Condition</td><td>The time of first treatment of the condition</td></tr><tr><td style="white-space:nowrap">hospital-admission<a name="evidence-variable-event-hospital-admission"> </a></td><td>Hospital Admission</td><td>The time of admission to the hospital</td></tr><tr><td style="white-space:nowrap">hospital-discharge<a name="evidence-variable-event-hospital-discharge"> </a></td><td>Hospital Discharge</td><td>The time of discharge from the hospital</td></tr><tr><td style="white-space:nowrap">operative-procedure<a name="evidence-variable-event-operative-procedure"> </a></td><td>Operative Procedure</td><td>The time of surgery</td></tr></table></div></text><extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-wg"><valueCode value="cds"/></extension><extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-standards-status"><valueCode value="normative"/></extension><extension url="http://hl7.org/fhir/StructureDefinition/structuredefinition-fmm"><valueInteger value="5"/></extension><url value="http://hl7.org/fhir/evidence-variable-event"/><identifier><system value="urn:ietf:rfc:3986"/><value value="urn:oid:2.16.840.1.113883.4.642.4.1955"/></identifier><version value="6.0.0-ballot4"/><name value="EvidenceVariableEvent"/><title value="Evidence Variable Event"/><status value="active"/><experimental value="false"/><date value="2021-01-05T10:01:24+11:00"/><publisher value="HL7 International / Clinical Decision Support"/><contact><telecom><system value="url"/><value value="http://hl7.org/fhir"/></telecom><telecom><system value="email"/><value value="fhir@lists.hl7.org"/></telecom></contact><contact><telecom><system value="url"/><value value="http://www.hl7.org/Special/committees/dss"/></telecom></contact><description value="The event used as a base point (reference point) in time."/><jurisdiction><coding><system value="http://unstats.un.org/unsd/methods/m49/m49.htm"/><code value="001"/><display value="World"/></coding></jurisdiction><caseSensitive value="true"/><valueSet value="http://hl7.org/fhir/ValueSet/evidence-variable-event"/><content value="complete"/><concept><code value="study-start"/><display value="Study Start"/><definition value="The time of enrollment for the study participant"/></concept><concept><code value="treatment-start"/><display value="Start of Treatment"/><definition value="The time of initiation of the treatment"/></concept><concept><code value="condition-detection"/><display value="Detection of Condition"/><definition value="The time of first detection of the condition"/></concept><concept><code value="condition-treatment"/><display value="Treatment of Condition"/><definition value="The time of first treatment of the condition"/></concept><concept><code value="hospital-admission"/><display value="Hospital Admission"/><definition value="The time of admission to the hospital"/></concept><concept><code value="hospital-discharge"/><display value="Hospital Discharge"/><definition value="The time of discharge from the hospital"/></concept><concept><code value="operative-procedure"/><display value="Operative Procedure"/><definition value="The time of surgery"/></concept></CodeSystem>