<status value="active" /> <date value="2026-02-25" /> <publisher value="HL7 UK" /> <contact> <name value="HL7 UK" /> <telecom> <system value="email" /> <value value="ukcore@hl7.org.uk" /> <use value="work" /> <rank value="1" /> </telecom> </contact> <description value="This profile defines the UK constraints and extensions on the International FHIR resource [Observation](https://hl7.org/fhir/R4/Observation.html), in order to represent an individual laboratory test and result value. These tests can be grouped together using the UKCore-Observation-Group-Lab profile." /> <purpose value="To provide the minimum expectations for each individual laboratory test." /> <copyright value="Copyright © 2021+ HL7 UK Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. HL7® FHIR® standard Copyright © 2011+ HL7 The HL7® FHIR® standard is used under the FHIR license. You may obtain a copy of the FHIR license at https://www.hl7.org/fhir/license.html." /> <fhirVersion value="4.0.1" /> <kind value="resource" /> <abstract value="false" /> <type value="Observation" /> <baseDefinition value="http://hl7.org/fhir/StructureDefinition/Observation" /> <derivation value="constraint" /> <differential> <element id="Observation"> <path value="Observation" /> <constraint> <key value="ukcore-obs-lab-001" /> <severity value="warning" /> <human value="Either `value`, `dataAbsentReason` or `note` SHOULD be populated" /> <expression value="value.exists() or dataAbsentReason.exists() or note.exists()" /> </constraint> </element> <element id="Observation.extension:ObservationOrganizer"> <path value="Observation.extension" /> <sliceName value="ObservationOrganizer" /> <type> <code value="Extension" /> <profile value="http://hl7.org/fhir/6.0/StructureDefinition/extension-Observation.organizer" /> </type> </element> <element id="Observation.status"> <path value="Observation.status" /> <short value="The status of the result value." /> <mustSupport value="true" /> </element> <element id="Observation.category"> <path value="Observation.category" /> <slicing> <discriminator> <type value="value" /> <path value="coding.code" /> </discriminator> <rules value="open" /> </slicing> <short value="A code that classifies the general type of observation being made." /> <min value="1" /> <mustSupport value="true" /> </element> <element id="Observation.category:laboratory"> <path value="Observation.category" /> <sliceName value="laboratory" /> <short value="A mandatory code, to identify this observation as being Lab related." /> <min value="1" /> <max value="1" /> <mustSupport value="true" /> </element> <element id="Observation.category:laboratory.coding.system"> <path value="Observation.category.coding.system" /> <fixedUri value="http://terminology.hl7.org/CodeSystem/observation-category" /> </element> <element id="Observation.category:laboratory.coding.code"> <path value="Observation.category.coding.code" /> <fixedCode value="laboratory" /> </element> <element id="Observation.code"> <path value="Observation.code" /> <short value="The type of lab related observation (code / type)." /> <mustSupport value="true" /> <binding> <strength value="preferred" /> <description value="A code from the SNOMED Clinical Terminology UK coding system regarding laboratory medicine test results" /> <valueSet value="https://fhir.hl7.org.uk/ValueSet/UKCore-PathologyAndLaboratoryMedicineObservables" /> </binding> </element> <element id="Observation.subject"> <path value="Observation.subject" /> <type> <code value="Reference" /> <targetProfile value="http://hl7.org/fhir/StructureDefinition/Patient" /> </type> </element> <element id="Observation.bodySite"> <path value="Observation.bodySite" /> <binding> <strength value="preferred" /> </binding> </element> <element id="Observation.method"> <path value="Observation.method" /> <binding> <strength value="preferred" /> </binding> </element> </differential> </StructureDefinition>