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Terminology

Healthcare terminology and coding systems are fundamental to interpreting medical data. These standardized vocabularies allow different healthcare systems to communicate effectively by using common codes and definitions for medical concepts.

#Overview

While standards exist, we've observed that healthcare payers often reference these systems inconsistently in their FHIR implementations.

For example, the official HL7 URI for ICD-10 is http://hl7.org/fhir/sid/icd-10, but you might encounter variants like https://icd.who.int/browse10/2019/en in some system fields in FHIR resources.

Flexpa's API addresses this challenge by:

  1. Fixing system references in the FHIR resources returned by our API to resolve to the official, standardized URI
  2. Validating with FHIR CodeSystem $lookup operations on terminology our systems process

Legend

HL7 lists several types of code systems. They can be categorized as:
  • Code system
    A system that is defined by HL7 FHIR
  • Naming system
    A curated namespace that is often used for the identification of concepts, people, devices, etc.
  • External code system
    A system that is defined by an organization that is external to, but referenced by, HL7. See HL7 External code systems
  • FHIR vendor
    A system that is defined by a FHIR vendor or implementer

Supported code systems

Flexpa's API attempts to map the following code systems in place within FHIR resource payloads. The mapped value is set to the system URI.
NameURIOther IDsCategorySource
ActCodehttp://terminology.hl7.org/CodeSystem/v3-ActCodeurn:oid:2.16.840.1.113883.5.4HL7
Adjudicationhttp://careevolution.com/fhir/AdjudicationCare Evolution
AdjudicationValueCodeshttp://terminology.hl7.org/CodeSystem/adjudicationurn:oid:2.16.840.1.113883.4.642.1.1171HL7
C4BBAdjudicationhttp://hl7.org/fhir/us/carin-bb/CodeSystem/C4BBAdjudicationCARIN Blue Button
C4BBAdjudicationDiscriminatorhttp://hl7.org/fhir/us/carin-bb/CodeSystem/C4BBAdjudicationDiscriminatorCARIN Blue Button
C4BBClaimDiagnosisTypehttp://hl7.org/fhir/us/carin-bb/CodeSystem/C4BBClaimDiagnosisTypeCARIN Blue Button
C4BBClaimProcedureTypehttp://hl7.org/fhir/us/carin-bb/CodeSystem/C4BBClaimProcedureTypeCARIN Blue Button
C4BBPayerAdjudicationStatushttp://hl7.org/fhir/us/carin-bb/CodeSystem/C4BBPayerAdjudicationStatusCARIN Blue Button
C4BBSupportingInfoTypehttp://hl7.org/fhir/us/carin-bb/CodeSystem/C4BBSupportingInfoTypeCARIN Blue Button
ClaimCareTeamRoleCodeshttp://terminology.hl7.org/CodeSystem/claimcareteamroleurn:oid:2.16.840.1.113883.4.642.1.1165HL7
ClaimInformationCategoryCodeshttp://terminology.hl7.org/CodeSystem/claiminformationcategoryurn:oid:2.16.840.1.113883.4.642.1.1163HL7
ClaimPayeeTypeCodeshttp://terminology.hl7.org/CodeSystem/payeetypeurn:oid:2.16.840.1.113883.4.642.1.1050HL7
ClaimTypeCodeshttp://terminology.hl7.org/CodeSystem/claim-typeurn:oid:2.16.840.1.113883.4.642.1.1156HL7
CoInsuranceOptionCShttp://hl7.org/fhir/us/davinci-drug-formulary/CodeSystem/usdf-CoinsuranceOptionCSDaVinci PDex US Drug Formulary
ContactEntityTypehttp://terminology.hl7.org/CodeSystem/contactentity-typeHL7
CopayOptionCShttp://hl7.org/fhir/us/davinci-drug-formulary/CodeSystem/usdf-CopayOptionCSDaVinci PDex US Drug Formulary
CoverageClassCodeshttp://terminology.hl7.org/CodeSystem/coverage-classurn:oid:2.16.840.1.113883.4.642.1.1147HL7
CPThttp://www.ama-assn.org/go/cpturn:oid:2.16.840.1.113883.6.12American Medical Association
DataAbsentReasonhttp://terminology.hl7.org/CodeSystem/data-absent-reasonurn:oid:2.16.840.1.113883.4.642.4.1048HL7
DiagnosticServiceSectionIDhttp://terminology.hl7.org/CodeSystem/v2-0074urn:oid:2.16.840.1.113883.18.29HL7
DrugTierCShttp://hl7.org/fhir/us/davinci-drug-formulary/CodeSystem/usdf-DrugTierCSDaVinci PDex US Drug Formulary
ExampleDiagnosisTypeCodeshttp://terminology.hl7.org/CodeSystem/ex-diagnosistypeurn:oid:2.16.840.1.113883.4.642.1.1167HL7
ExampleServicePlaceCodeshttp://terminology.hl7.org/CodeSystem/ex-serviceplaceurn:oid:2.16.840.1.113883.4.642.1.1157HL7
ICD-10http://hl7.org/fhir/sid/icd-10urn:oid:2.16.840.1.113883.6.3World Health Organization
ICD-10-CMhttp://hl7.org/fhir/sid/icd-10-cmurn:oid:2.16.840.1.113883.6.90World Health Organization
ICD-9-CMhttp://terminology.hl7.org/CodeSystem/icd9cmurn:oid:2.16.840.1.113883.6.2World Health Organization
Icd10PCShttp://terminology.hl7.org/CodeSystem/icd10PCSurn:oid:2.16.840.1.113883.6.4CMS
IdentifierTypehttp://terminology.hl7.org/CodeSystem/v2-0203urn:oid:2.16.840.1.113883.18.108HL7
MDCurn:iso:std:iso:11073:10101urn:oid:2.16.840.1.113883.6.24International Organization for Standardization
MED-RThttp://va.gov/terminology/medrturn:oid:2.16.840.1.113883.6.345National Library of Medicine
NDChttp://hl7.org/fhir/sid/ndcurn:oid:2.16.840.1.113883.6.69US Food and Drug Administration
NDF-RThttp://hl7.org/fhir/ndfrturn:oid:2.16.840.1.113883.6.209US Department of Veterans Affairs, Veterans Health Administration
NPIhttp://hl7.org/fhir/sid/us-npiurn:oid:2.16.840.1.113883.4.6HL7
NuccProviderCodeshttp://nucc.org/provider-taxonomyHL7
NullFlavorhttp://terminology.hl7.org/CodeSystem/v3-NullFlavorHL7
ObservationCategoryCodeshttp://terminology.hl7.org/CodeSystem/observation-categoryurn:oid:2.16.840.1.113883.4.642.1.1125HL7
OrganizationTypehttp://terminology.hl7.org/CodeSystem/organization-typeurn:oid:2.16.840.1.113883.4.642.1.1128HL7
PatientIdhttp://careevolution.com/fhir/PatientIdCare Evolution
pCLOCDhttps://fhir.infoway-inforoute.ca/CodeSystem/pCLOCDurn:oid:2.16.840.1.113883.2.20.5.1Canada Health Infoway
RxNormhttp://www.nlm.nih.gov/research/umls/rxnormurn:oid:2.16.840.1.113883.6.88National Library of Medicine
SNOMEDhttp://snomed.info/scturn:oid:2.16.840.1.113883.6.96IHTSDO / SNOMED International
SubscriberRelationshipCodeshttp://terminology.hl7.org/CodeSystem/subscriber-relationshipurn:oid:2.16.840.1.113883.4.642.1.1386HL7
UCUMhttp://unitsofmeasure.orgurn:oid:2.16.840.1.113883.6.8Regenstrief Institute, Inc.
UNIIhttp://fdasis.nlm.nih.govurn:oid:2.16.840.1.113883.4.9US Food and Drug Administration
UPChttp://terminology.hl7.org/CodeSystem/UPCurn:oid:2.16.840.1.113883.6.55GS1
USEINhttp://terminology.hl7.org/NamingSystem/USEINurn:oid:2.16.840.1.113883.4.4HL7
USPShttps://www.usps.comUnited States Postal Service
Total 47
Note: If you require a specific code system to be supported, contact support@flexpa.com.
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