# DK Core, MedCom messaging and sundhed.dk: three Danish FHIR products > DK Core 3.7.0 is the HL7 Denmark baseline. MedCom FHIR messaging and the sundhed.dk eHealth Infrastructure are different products. CPR uses urn:oid:1.2.208.176.1.2. Do not collapse them into one Danish FHIR server. Author: Ala Ben Aicha Canonical page: https://alabenaicha.me/insights/fhir-dk-core-medcom Updated: 2026-09-19 ## Direct answer DK Core 3.7.0 is the HL7 Denmark baseline. MedCom FHIR messaging and the sundhed.dk eHealth Infrastructure IG are different products. CPR uses urn:oid:1.2.208.176.1.2. ## Three publications, three buyers Danish FHIR work is easy to flatten into “dk-core”. HL7 Denmark, MedCom and the national telemedicine infrastructure publish different implementation guides. A CareCommunication message is not an eHealth CarePlan API, and neither is a substitute for DK Core Patient. | Layer | Owner / home | Canonical / package | What it is | What it is not | | -------------------------------------------------------- | ------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------- | | **DK Core** 3.7.0 (release, 30 May 2026) | HL7 Denmark; [hl7.dk/fhir/core](https://hl7.dk/fhir/core) | Official URL `http://hl7.dk/fhir/core/ImplementationGuide/hl7.fhir.dk.core`; package `hl7.fhir.dk.core#3.7.0` on FHIR R4 | National **base** for identifiers, Patient, Organization, Observation and related profiles. Listed in the Danish Health Data Authority standard catalogue after RUSA | Not a FHIR API specification yet (the IG says so), not MedCom messaging | | **MedCom Core / messaging** | MedCom; [medcomfhir.dk/ig](http://medcomfhir.dk/ig/) | MedCom Core official URL `http://medcomfhir.dk/ig/core/ImplementationGuide/medcom.fhir.dk.core`; package family `medcom.fhir.dk.core`. Messaging, HospitalNotification, CareCommunication are separate IGs | **Message** exchange (hospital notification, correspondence, acknowledgement) replacing older VANS/EDIFACT-era MedCom standards over time | Not DK Core, not a REST EHR, not sundhed.dk telemedicine | | **eHealth Infrastructure** 10.0.1 (release, 11 Aug 2026) | Den telemedicinske infrastruktur; [ehealth.sundhed.dk/fhir](http://ehealth.sundhed.dk/fhir) | Official URL `http://ehealth.sundhed.dk/fhir/ImplementationGuide/dk.ehealth.sundhed.fhir.ig.core`; package `dk.ehealth.sundhed.fhir.ig.core#10.0.1` | National **telemedicine** FHIR platform (CarePlan, infrastructure operations) | Not MedCom hospital messaging, not a generic national EHR | Primary sources: [DK Core 3.7.0](https://hl7.dk/fhir/core) (published package; prefer this over `build.fhir.org/ig/hl7dk/dk-core`), [MedCom IG index](http://medcomfhir.dk/ig/), [eHealth Infrastructure 10.0.1](http://ehealth.sundhed.dk/fhir). CI builds of MedCom (for example `build.fhir.org/ig/medcomdk/dk-medcom-core`) change; pin the published package the buyer names. DK Core 3.7.0 is the current published release as of write day. Do not implement the 3.6.0/3.5.0 trees unless the contract freezes them. ## The identifier: CPR Country-specific identifier for Danish Patient is the Central Person Register number. DK Core datatype [DkCoreCprIdentifier](https://hl7.dk/fhir/core/StructureDefinition-dk-core-cpr-identifier.html) fixes: `urn:oid:1.2.208.176.1.2` Ten digits, `use` official, with a CPR format invariant. MedCom Core Patient also requires CPR or eCPR. Replacement identifiers (X-eCPR, D-eCPR) are separate DK Core identifier profiles — they are not CPR. Do not publish a real CPR. Keep the system URL and a dummy value in fixtures. SOR-id identifies organisations. It does not identify patients. ## What to implement first 1. If the buyer needs a **Danish Patient / identifier pack**: DK Core 3.7.0, CPR system as above, package `hl7.fhir.dk.core#3.7.0`. 2. If the buyer is replacing **MedCom correspondence or hospital notification**: the named MedCom messaging IG (CareCommunication, HospitalNotification, Acknowledgement), not the eHealth Infrastructure. 3. If the buyer is on **sundhed.dk telemedicine**: eHealth Infrastructure 10.0.1. It depends on DK Core; it is not MedCom. 4. For EHDS payloads, overlay [EU Core](https://alabenaicha.me/insights/fhir-eu-core-ehds-implementation). Neighbouring [NLL](https://alabenaicha.me/insights/fhir-se-national-medication-list) is a Swedish medication-list API, not a Danish equivalent. The [HL7 FHIR R4 integration guide](https://alabenaicha.me/insights/hl7-fhir-integration-guide) is the generic REST primer. MedCom MessageHeader rules override it. ## What this is not This article is not MedCom approval, not a Sundhedsdatastyrelsen certificate, not eHealth Infrastructure onboarding, and not legal advice. Implementing DK Core profiles does not enrol you in MedCom or in the telemedicine infrastructure. I do not operate those environments. Nothing here is clinical advice. ## Related reading * [Swedish National Medication List](https://alabenaicha.me/insights/fhir-se-national-medication-list) * [EU Core and EHDS](https://alabenaicha.me/insights/fhir-eu-core-ehds-implementation) * [FHIR implementation guides by country](https://alabenaicha.me/insights/fhir-implementation-guides-by-country) For mapping work against DK Core or MedCom, use [HL7 FHIR integration](https://alabenaicha.me/services/hl7-fhir-integration) or [start a project](https://alabenaicha.me/contact?intent=project).