SNOMED CT March 2025 International Edition - SNOMED International Release notes
Introduction
Background
SNOMED CT terminology provides a common language that enables a consistent way of indexing, storing, retrieving, and aggregating clinical data across specialties and sites of care.
SNOMED International maintains the SNOMED CT technical design, the content architecture, the SNOMED CT content (includes the concepts table, the descriptions table, the relationships table, a history table, and ICD mappings), and related technical documentation.
Purpose
This document provides a summarized description of the content changes included in the March 2025 release of SNOMED Clinical Terms® (SCT) International Edition.
It also includes notes detailing the known content or technical issues where the root cause is understood, the fix has been discussed and agreed to, but has yet to be implemented.
The SNOMED International release notes are available alongside the March 2025 International Edition.
Scope
This document is written for the purpose described above and is not intended to provide details of the technical specifications for SNOMED CT or encompass every change made.
Audience
The audience includes National Release Centers, WHO-FIC release centers, vendors of electronic health records, terminology developers and managers who wish to have an understanding of changes that have been incorporated into the March 2025 International Edition.
Please note, you may have to register for a Confluence user account in order to access the links included in these release notes.
Content Development Activity
Summary
Continuous quality improvement and enhancement of existing content is an ongoing process undertaken by SNOMED International in preparation for every release. The March 2025 International Edition has seen a continuation of the work driven by contributions from: Kaiser Permanente i.e. Convergent Medical Terminology (CMT), Global Medical Device Nomenclature Agency (GMDNA), Orphanet and other domain specific collaborations as well as requests received via the Content Request System (CRS).
Additionally quality improvement activities are advanced via project driven initiatives summarized below. Additional work items impacting every release are updates to the SNOMED CT derived maps such as ICD-10 and ICD-O; details are included in these release notes.
Information about editorial decisions may be found in the SNOMED CT Editorial Guide; mapping guidance for ICD-10 can be found here.
Quality Initiative
The Quality Initiative (QI) project is the implementation of the Quality Strategy. After a successful pilot project for the July 2018 Edition release, the next stage has been implemented for subsequent releases including March 2025.
Quality improvement tasks are being deployed to improve internal structural consistency and ensure compliance with editorial policy related to the stated modeling of content. Additionally, correction or addition of defining relationships is being carried out to accurately reflect current clinical knowledge and ensure the semantic reliability of descriptions associated with a concept.
Revision 240279008 |Fetoscopic procedure (procedure)|
Added inspection role group to 240279008 |Fetoscopic procedure (procedure)| and subtypes to facilitate appropriate classification.
Method = inspection
Using device = fetoscope
Occurrence = fetal period
Body Structure
Inactivation of 46141003|Structure of alveolus dentalis (body structure)|
Working in consultation with the Dentistry Clinical Reference Group, 46141003 |Structure of alveolus dentalis (body structure)| and 1240400004 |Structure of tooth socket (body structure)| have been identified as duplicate concepts.
46141003|Structure of alveolus dentalis (body structure)| has been inactivated with historical association to 1240400004|Structure of tooth socket (body structure)|.
Additional changes have been made to concepts which had been modeled with site 46141003|Structure of alveolus dentalis (body structure)|, the model for these concepts has been updated to include site 1240400004|Structure of tooth socket (body structure)|.
Number of concepts edited (approx): 16
Revision 17176004|Structure of bridge of nose (body structure)| and 84047001|Structure of dorsum of nose (body structure)|
A text definition has been added to the concepts 17176004|Structure of bridge of nose (body structure)| and 84047001|Structure of dorsum of nose (body structure)|.
Regions of the external nose have been reorganized.
Number of concepts edited (approx): 33
SEP and Laterality Anatomy Reference Sets
The release file for the lateralizable body structure reference set has been updated and validated.
The release file for the SEP reference set has been updated and validated.
Procedure
Radiographic Imaging
Work is progressing for this content tracker for information please see the informational briefing note here.
Situation with Explicit Context
Update Descriptions
The fully specified name and preferred term for descendants of 41769001 |Disease suspected (situation)| have been updated to the agreed pattern of 'X disorder/finding' before the word 'suspected' to improve consistency in this hierarchy.
Number of concepts edited (approx): 150
Collaboration/Harmonization Agreements
Convergent Medical Terminology (CMT)
41 new concepts have been added for the ophthalmology domain.
Orphanet
Working in collaboration with Orphanet efforts are ongoing to update rare disease concepts in SNOMED CT to maintain alignment with Orphanet for the annual update of the SNOMED CT to Orphanet Maps.
Work has commenced to annotate content added for the Orphanet project with attribution to Inserm Orphanet. As part of this effort, textual definitions for concepts previously added for the Orphanet project have been updated to align with the current published version of the Orphanet definition. This has resulted in published text definitions being inactivated and replaced in bulk and this work has been completed for the March 2025 release. There remains approximately 200 concepts with text definition that will be updated to include attribution.
All of the concepts added for the Orphanet project have been mapped to ICD-10.
Gravity
Work for this project is ongoing.
Nursing
Five concepts have been added to support the domain of nursing.
Cancer Synoptic Reporting
Cancer synoptic reports are used by many member countries to record pathology examination of cancer specimens including the College of American Pathologists (US and Canada), Royal College of Pathology (UK), Royal College of Pathology Australasia (Australia, New Zealand), PALGA (The Netherlands), Swedish Society of Pathology, and others.
For more information about this project, please see Cancer Synoptic Reporting Clinical Project Group
International League Against Epilepsy (ILAE)
In line with approved harmonized terminology, this project is working on alignment including restructuring to update the hierarchy << 313307000 |Epileptic seizure (finding)|.
Further information about the project is available here
Internal Quality Improvement
Machine Readable Concept Model (MRCM) Changes
There have been no changes for the MRCM in the March 2025 International Edition.
Future changes that are currently in progress can be viewed via the MRCM Daily Build Browser
Please see Early Visibility Release Notifications for future planned changes to MRCM.
Annotation Reference Set
The addition of content for the Annotations refset was commenced in the July 2024 International Edition release and is ongoing for attribution of text definition to organizations with a collaboration agreement, starting with Inserm Orphanet.
SNOMED CT derived products
ICD-10 map
The SNOMED CT to the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (© World Health Organization 1994) 2016 Version map (SNOMED CT to ICD-10 Map) is included in the SNOMED CT International Edition as a Baseline. The SNOMED CT to ICD-10 Map was created to support the epidemiological, statistical and administrative reporting needs of SNOMED International member countries and WHO Collaborating Centers.
The SNOMED CT to ICD-10 Map is released in Release Format 2 (RF2) only. It is located in the file der2_iisssccRefset_ExtendedMapFull_INT_20200731.txt, which is in the Map folder under Refset, in each of the three RF2 Release Type folders.
The SNOMED CT to ICD-10 Map is released as Refset 447562003 |SNOMED CT to ICD-10 extended map (foundation metadata concept).
The ICD-10 Mapping Technical Guide (including exemplars) is hosted here https://confluence.ihtsdotools.org/display/DOCICD10
Content Development Activity Summary
The map is a directed set of relationships from SNOMED CT source concepts to ICD-10 target classification codes. The SNOMED CT source domains for the MAP are limited to subtypes of 404684003 |clinical finding|, 272379006 |event| and 243796009 |situation with explicit context|. The target classification codes are ICD-10 2016 release.
Mapped content for March 2025
The map provided for the March 2025 International Edition has been updated, and now represents a complete map from SNOMED CT International Edition to ICD-10 2016 version.
501 newly authored concepts have been added and mapped.
The SNOMED to ICD-O (morphology) map has zero additional concepts added as a result of the ICD-O 3.2 review or added due to CRS requests.
We would welcome feedback on any issues that users of the map may detect when using the map. Issues should be submitted via mapping@snomed.org
SNOMED CT to OWL conversion and classification
The repository containing the toolkit enabling simple SNOMED CT to OWL conversion and classification can be found here, including documentation on its use: https://github.com/IHTSDO/snomed-owl-toolkit
Please contact SNOMED International at support@snomed.org if you would like to provide any feedback on ways to extend and improve the new toolkit.
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