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  <xs:element id="lh_Shorttermdebtissuancecosts" abstract="false" name="Shorttermdebtissuancecosts" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_SwapTypeAxis" abstract="true" name="SwapTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="lh_DiagnosticsMember" abstract="true" name="DiagnosticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_CashPaidDuringPeriodForAbstract" abstract="true" name="CashPaidDuringPeriodForAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="lh_OthercountriesMember" abstract="true" name="OthercountriesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_CommonSharesIssuedRollforwardAbstract" abstract="true" name="CommonSharesIssuedRollforwardAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="lh_CommonSharesOutstandingRollforwardAbstract" abstract="true" name="CommonSharesOutstandingRollforwardAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="lh_DisposalGroupIncludingDiscontinuedOperationFortreaDistribution" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationFortreaDistribution" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_InterestPaidInCash" abstract="false" name="InterestPaidInCash" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_Issuanceofcommonstockunderemployeeplans" abstract="false" name="Issuanceofcommonstockunderemployeeplans" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_A470SeniorNotesDue2045" abstract="false" name="A470SeniorNotesDue2045" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_OtherAcquisitionsMember" abstract="true" name="OtherAcquisitionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="lh_OtheracquireesMember" abstract="true" name="OtheracquireesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_ClientMember" abstract="true" name="ClientMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_DisposalGroupIncludingDiscontinuedOperationFortreaSeniorNotesInterestRate" abstract="false" name="DisposalGroupIncludingDiscontinuedOperationFortreaSeniorNotesInterestRate" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="lh_NetProceedsFromIssuanceOfStockToEmployees" abstract="false" name="NetProceedsFromIssuanceOfStockToEmployees" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_LabCorpDiagnosticsMember" abstract="true" name="LabCorpDiagnosticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_SeniorNotesDue2031Member" abstract="true" name="SeniorNotesDue2031Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_A2018SwapAgreementsMember" abstract="true" name="A2018SwapAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="lh_AllowanceforCreditLoss" abstract="false" name="AllowanceforCreditLoss" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="lh_ProvidenceHealthMember" abstract="true" name="ProvidenceHealthMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
