HL7 FHIR Implementation Guide: DK Core
2.2.0 - release Denmark flag

This page is part of the HL7 FHIR Implementation Guide: DK Core (v2.2.0: Release) based on FHIR R4. This is the current published version in its permanent home (it will always be available at this URL). For a full list of available versions, see the Directory of published versions


Official URL: http://hl7.dk/fhir/core/ImplementationGuide/hl7.fhir.dk.core Version: 2.2.0
Active as of 2023-05-05 Computable Name: DKCore


This implementation guide is provided to support the use of FHIR®© in a Danish context.

This document is a working specification that is expected to be implemented and tested by FHIR®© system producers to enable feedback to improve the content of this guide. With this first Standard for Trial Use ballot version we are looking for feedback if the following goals are met:

  • provide guidance on core resources for identifiers, code system, value sets and naming systems in a Danish specific context.
  • define extensions that are necessary for local use covering needed Danish concepts

Note: This implementation guide is not (yet) a FHIR API specification, this will be a goal for the next iteration.


The target group of this specification is any party that wants to specify FHIR standards for use in the Danish Health Sector. As a core-specification, a party that wants to use the specification should inherit from dk-core and build use-case specific profiles on top. As such, dk-core does not provide profiles for specific use use cases out-of-the-box.

This document presents Danish use concepts defined via FHIR processable artefacts:

  • Profiles - are useful constraints of core FHIR resources and datatype for Danish use
  • Extensions - are FHIR extensions that are added for local use, covering needed Danish concepts
  • Terminologies - are defined or referenced code systems and value sets for Danish context

dk-core is regularily approved by HL7 Denmark and added to the catalogue of approved standards governed by The Danish Health Data Authority, after consideration by RUSA (Rådgivende Udvalg for Standarder og Arkitektur). See the exact approvals for each version in the history page.


FHIR profiles are managed under HL7 Denmark in the HL7 Danish FHIR working group:


This guide is the product of collaborative work undertaken with participants from:


The main language of this implementation guide, and the profiles in it, is English. Content that does not have an official English term uses a Danish term instead. Sometimes terms are expalined using both Danish and English. Danish terms and explanaitions are prefixed with ‘Da’

Connection between dk-core and common Danish architectures and standards

HL7 Denmark includes common Danish architectures and standards if relevant, when content is added to dk-core. This section provides information about principle decisions as well as more specific ones that require explainantion.

Principle decisions

  • HL7 Denmark considers Danish legislation as the first source of truth when designing models, HL7 Denmark seeks to represent known named entities relevant for health data interoperability truthfully.
  • HL7 Denmark upholds the requirements of the FHIR standard whenever it is possible within the bounderies of the Danish legislation.
  • Enitites that are named both in the FHIR standard and Danish legislation, keeps FHIR naming and requirements, but should explain its relation to Danish names/requirements.
  • Danish standards and arhitectures are considered when designing FHIR profiles. HL7 Denmark uses them when they are relevant for interoperability of health data, and when they are compatiple with the FHIR standard. Often public information and data models used as basis of public registries are too detailed, to warrant replication in a FHIR standard. E.g. The Organization profile references organisation registries such as SOR and FK-ORG rather than re-constructing each of their attributes in the FHIR-profile, only attributes relevant for interoperability is provided in the FHIR profiles.

Specific decisions

  • Patient.maritalStatus uses the extendable ValueSet required by the FHIR standard. However, Danish legislation and registries have two additional statuses not covered by the international ValueSet, so these two codes are added in dk-core.
  • Several basic resources such as Patient and Organization has an adress. In dk-core these adresses use the FHIR datatype, which is very basic compared to the Danish Adress standard. However, adresses can be refered faithfully using the international standard e.g. Adress.text can be mapped directly to the Danish Adresse.adressebetegnelse. If more details are needed than FHIR instanses provide, the Danish adress registry can be used for look-up.

Safety Considerations

This implementation guide defines data elements, resources, formats, and methods for exchanging healthcare data between different participants in the healthcare process. As such, clinical safety is a key concern. Additional guidance regarding safety for the specification’s many and various implementations is available at: https://www.hl7.org/FHIR/safety.html.

Although the present specification does gives users the opportunity to observe data protection and data security regulations, its use does not guarantee compliance with these regulations. Effective compliance must be ensured by appropriate measures during implementation projects and in daily operations. The corresponding implementation measures are explained in the standard. In addition, the present specification can only influence compliance with the security regulations in the technical area of standardisation. It cannot influence organisational and contractual matters.

This document is licensed under Creative Commons “No Rights Reserved” (CC0).

HL7®, HEALTH LEVEL SEVEN®, FHIR® and the FHIR ® are trademarks owned by Health Level Seven International, registered with the United States Patent and Trademark Office.

This implementation guide contains and references intellectual property owned by third parties (“Third Party IP”). Acceptance of these License Terms does not grant any rights with respect to Third Party IP. The licensee alone is responsible for identifying and obtaining any necessary licenses or authorizations to utilize Third Party IP in connection with the specification or otherwise.

See also http://hl7.org/fhir/license.html

Following is a non-exhaustive list of third-party artifacts and terminologies that may require a separate license:

SNOMED Clinical Terms® (SNOMED CT®) This material includes SNOMED Clinical Terms® (SNOMED CT®) which is used by permission of SNOMED International (former known as International Health Terminology Standards Development Organisation IHTSDO). All rights reserved. SNOMED CT®, was originally created by The College of American Pathologists. “SNOMED” and “SNOMED CT” are registered trademarks of SNOMED International.

Logical Observation Identifiers Names and Codes LOINC This material contains content from LOINC® (http://loinc.org). The LOINC table, LOINC codes, and LOINC panels and forms file are copyright © 1995-2013, Regenstrief Institute, Inc. and the Logical Observation Identifiers Names and Codes (LOINC) Committee and available at no cost under the license at http://loinc.org/terms-of-use.

IP Statements

This publication includes IP covered under the following statements.

Cross Version Analysis

This is an R4 IG. None of the features it uses are changed in R4B, so it can be used as is with R4B systems. Packages for both R4 (hl7.fhir.dk.core.r4) and R4B (hl7.fhir.dk.core.r4b) are available.

Dependency Table

.. HL7 FHIR Implementation Guide: DK Corehl7.fhir.dk.core#2.2.0R4
... HL7 Terminology (THO)hl7.terminology.r4#5.0.0R4Automatically added as a dependency - all IGs depend on HL7 Terminology
... Personal Health Device Implementation Guidehl7.fhir.uv.phd#1.0.0R4
.... HL7 Terminology (THO)hl7.terminology.r4#3.1.0R4

Package hl7.fhir.uv.phd#1.0.0

ImplementationGuide for Personal Health Devices (PHD), used in remote patient monitoring (e.g., weight scales, blood pressure cuffs, glucose monitors, pulse-oximeters, etc.). (built Thu, May 12, 2022 20:20+0000+00:00)

Globals Table

There are no Global profiles defined