Introduction

This IG defines the extensions that are globally defined and available in all FHIR implementation contexts. Prior to R5 these extensions were defined in the core specification, but starting from R5 they have been moved out of the specification into a separate extensions pack so that the extensions can be updated more often than the base specification. This extension pack also defines some search parameters for the extensions.

In addition, the extension pack also contains a series of mapping language scripts that provide a formal executable definition of the relationship between R5 and the prior versions R4 and R4B. These are located in the extension pack to allow them to also be updated as they are tested and used in production and improvements are made.

Content Registries

• Extension Registry
• Search Parameters for the Extensions
• R5/R4(B) Conversion Registry

Update Policy

Extensions

References to the extensions defined in this extension pack are found in Extension.url or in profile references to defined extensions in ElementDefinition.type.profile. While the profile references may be versioned using canonical versioned references, the most important references are in Extension.url and these are version-less.

For this reason, the extensions defined in this extension pack are managed very conservatively with regard to breaking changes:

• Extensions that are active are not subject to breaking changes. New extensions will be introduced if necessary
• Extensions labelled 'draft' may have breaking changes if the FHIR Management Group is satisfied that they are not in use in production, or if all the existing users are agree to making the change. The exact rules and processes still being discussed, but not all 'draft' extensions are subject to change
• In this regard, the definitions for breaking change to Normative artifacts apply. Note that the focus of these rules is preserving the validity and meaning of existing extensions, not preventing applications processing extensions from having to change
• The extensions all have the status of 'trial-use' but once they are active they are treated as normative. The FHIR Management Group has not yet decided how these extensions will be balloted in the future

Conversion Maps

The implementation scope of the conversion maps is fixed: implementing a proper transform from R4/R4B to R5 and vice versa. Ongoing changes may be made to the maps if they improve the mappings within this scope, including catering for common extensions.

Intellectual Property Considerations

This implementation guide and the underlying FHIR specification are licensed as public domain under the FHIR license. The license page also describes rules for the use of the FHIR name and logo.

This guide includes extensions making use of terminologies such as LOINC and SNOMED CT that have more restrictive licensing requirements. Implementers should make themselves familiar with licensing and any other constraints of terminologies used as part of their implementation process. In some cases, licensing requirements may limit the systems that data captured using certain codes may be shared with.

This publication includes IP covered under the following statements.

• Copyright HL7. Licensed under creative commons public domain
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  • priority: SpecCollectionPriority and SpecimenCollectionPriority
  • natureOfAbnormalTesting: ObsNatureAbnormal
  • commentType: AnnotationType
  • arrivalMode: EncModeOfArrival
  • nameAssemblyOrder: AssemblyOrder and HumanNameAssemblyOrder
  • specimenType: ObsSpecimenCode
• ISO Maintains the copyright on the country codes, and controls it's use carefully. For futher details see the ISO 3166 web page: https://www.iso.org/iso-3166-country-codes.html
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  • ISO 3166-1 Codes for the representation of names of countries and their subdivisions — Part 1: Country code: ArtifactJurisdiction, BestPractice and RecordedSexOrGender
• The UCUM codes, UCUM table (regardless of format), and UCUM Specification are copyright 1999-2009, Regenstrief Institute, Inc. and the Unified Codes for Units of Measures (UCUM) Organization. All rights reserved. https://ucum.org/trac/wiki/TermsOfUse
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  • Unified Code for Units of Measure (UCUM): AllowedUnits
• These codes are excerpted from ASTM Standard, E1762-95(2013) - Standard Guide for Electronic Authentication of Health Care Information, Copyright by ASTM International, 100 Barr Harbor Drive, West Conshohocken, PA 19428. Copies of this standard are available through the ASTM Web Site at www.astm.org.
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  • ASTM Signature Type Codes: QSignatureRequired
• These codes are excerpted from Digital Imaging and Communications in Medicine (DICOM) Standard, Part 16: Content Mapping Resource, Copyright © 2011 by the National Electrical Manufacturers Association.
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  • DICOM Audit Message Record Lifecycle Events: AELifecycle and ObjectLifecycleEvents
• These codes are excerpted from ETSI Standard for Digital Signatures and XAdES, Copyright by ETSI International. Copies of this standard are available through the ETSI Web Site at www.etsi.org.
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  • ETSI Signature Type Codes: QSignatureRequired
• These codes are excerpted from ISO Standard, TS 21089-2017 - Health Informatics - Trusted End-to-End Information Flows, Copyright by ISO International. Copies of this standard are available through the ISO Web Site at www.iso.org.
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  • ISO 21089 2017 Health Record Lifecycle Events: AELifecycle and ObjectLifecycleEvents
• This material contains content from LOINC. LOINC is copyright © 1995-2020, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and is available at no cost under the license. LOINC® is a registered United States trademark of Regenstrief Institute, Inc.
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  • LOINC: DataElementSDCObjectClass, DataElementSDCObjectClassProperty... Show 4 more, ObjectClass, ObjectClassProperty, Pronouns and RecordedSexOrGender
• This material contains content that is copyright of SNOMED International. Implementers of these specifications must have the appropriate SNOMED CT Affiliate license - for more information contact https://www.snomed.org/get-snomed or info@snomed.org.
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  • SNOMED Clinical Terms® (SNOMED CT®): AILocation, AISubstanceExposureRisk... Show 31 more, AnimalBreeds, AnimalSpecies, BDPManipulation, BDPProcessing, Barrier, BestPractice, ConditionCauseCodes, ConditionCourseCodes, ConditionDiseaseCourse, ConditionDueTo, ConditionOccurredFollowing, ConditionOutcome, ConditionPredecessorCodes, DataElementSDCObjectClass, DataElementSDCObjectClassProperty, FMHSeverity, FeedingDeviceCodes, FocalSubjectCodes, NttAdaptiveFeedingDevice, ObjectClass, ObjectClassProperty, ObsDeviceCode, ObsFocusCode, PGenderIdentity, PRAnimalSpecies, PatAnimal, ProtectiveFactor, SpecimenAdditive, SpecimenAdditiveSubstanceCodes, WorkflowBarrier and WorkflowReason
• Using RxNorm codes of type SAB=RXNORM as this specification describes does not require a UMLS license. Access to the full set of RxNorm definitions, and/or additional use of other RxNorm structures and information requires a UMLS license. The use of RxNorm in this specification is pursuant to HL7's status as a licensee of the NLM UMLS. HL7's license does not convey the right to use RxNorm to any users of this specification; implementers must acquire a license to use RxNorm in their own right.
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  • RxNorm: DataElementSDCObjectClass, DataElementSDCObjectClassProperty, ObjectClass and ObjectClassProperty