Introduction

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.

The International Health Terminology Standards Development organisation (IHTSDO^®), trading as 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.

The SNOMED CT Switzerland Extension - packages these components for release every December and July, to be used with the latest SNOMED CT International Edition release.

The same content can be viewed online using the SNOMED CT browser.

Background

This document provides a summarized description of the content changes included in the June 2023 Production release of the SNOMED Clinical Terms^® Managed Service Switzerland Extension package.

It will also include technical notes detailing the known issues which have been identified (should any of these exist). These are content or technical issues where the root cause is understood, and the fix has been discussed and agreed, but has yet to be implemented.

This Switzerland Extension package is dependent upon, and should therefore be consumed in conjunction with, the SNOMED CT® April 2023 International Edition release.

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 during the release.

Content Development Activity

Summary

Content from the SNOMED CT® April 2023 International Edition release has been included, alongside additional components for use in Switzerland. 

This extension contains concepts, relationships and reference sets for healthcare professionals. 

New and Updated Content

New content in this release:

This release contains translations from the Common French Translation and Common German Translation.

Technical notes

The Common French terms are in the Description files, but the Language Refset records for each Common French preference are not included in the Swiss Release Package. This leads to some gaps in the resolution of the dependencies. To reconcile the dependencies we recommend to download the Canadian edition of SNOMED CT alongside the Swiss Extension.

Known Issues

Known Issues are content or technical issues where the root cause is understood, and the resolution has been discussed and agreed but has yet to be implemented.  This can be due to a number of reasons, from lack of capacity within the current editing cycle, to the risk of impact to the stability of SNOMED CT if the fix were to be deployed at that stage in the Product lifecycle.  

For the SNOMED CT Managed Service - Switzerland Extension Release, the following Known Issues were identified, and agreed to be resolved in the next editing cycle:

Resolved Issues

Resolved Issues are those where the resolution has been discussed and agreed, and has been implemented in time for this release. 

For the SNOMED CT Managed Service - Switzerland Extension Release, the following Issues were Resolved: 

Notice of changes to the Switzerland Extension Release package

In order to implement an improved solution to the inclusion of the Common French and Common German content, the Switzerland Extension release package has been refined as follows from the June 2023 Release onwards:

• The complete set of Common German terms have now also been imported alongside the Common French terms.

• All historical records have been removed, and the June 2023 Release package will start as if it is a new "first time" release.  This entails the following changes: 

  • The June 2023 package contains all of the latest active content from this current cycle, plus all previous authoring cycles of the Switzerland Extension.

  • However, all historical records have been removed, which practically means that the Snapshot and Full files will contain identical content, as if this is the first Switzerland Extension release.

  • This also means that all inactive content has been removed from the Snapshot files (concept, relationship, language refset files, etc), as it has been deemed not useful to the end users, given that it relates to either inactive concepts, or the Common French module (which has now been completely removed from the Switzerland Extension package).

  • The only exception to this is the Description files which will contain some inactive records from the historical releases, due to them being potentially useful for users.  

• All Common French and Common German components have been moved into the Switzerland Extension Module (2011000195101).

  • All records and references to the Common French module (11000241103) which was previously included in the Switzerland Extension as a dependency, have therefore now been removed.  

  • The only exception to this are the FSN's in the original Common French repository, which are intentionally not included in any Extension release.

• Users should therefore use the Snapshot files for this first release in the new format (20230607) - from the next Switzerland release onwards the Full files will once again become useful from a historical data perspective.

Notice of changes to the International Edition Release Schedule

As you may already know SNOMED International have transitioned to a monthly delivery schedule for the International Edition of SNOMED CT. The move towards more frequent releases of SNOMED CT realizes several benefits, including:

• The potential to be able to get content changes into the terminology in a shorter time frame.

• The fostering of better interoperability, as a result of entities being able to consume release content that is more aligned with other organizations.

• The prevention of circular dependencies that occur in longer projects, due to the move towards smaller, more manageable authoring projects.

• More automated validation services, as a result of the inherent removal of the Alpha/Beta stages in the Release cycle.

Whilst most users will continue unaffected (as they can simply continue to download the releases every 6 months as always), this transition will necessarily involve a few changes to process/packages:

• Delta files have been removed from both International and Managed Service release packages, including the Switzerland Extension.  A Delta Generation service has been provided for those who need it. The Delta Generation Tool allows users to create their own Delta between two fixed release dates - you can find it here:

  • https://github.com/IHTSDO/delta-generator-tool/releases

• The ICD-O/ICD-10 Maps continues to be published in each Monthly International Edition release package (in line with that month's content) for the foreseeable future, unless we experience issues with the new process in Production, and they need to be removed at a later date.

The first monthly Release of the SNOMED CT International Edition was published on the 28th February 2022 with the Delta files having been removed, and therefore Delta files were also removed from the Switzerland Extension from the June 2022 Release onwards.

Please note - While the SNOMED CT International Edition is moving to monthly releases, the Switzerland Extension of SNOMED CT will remain on the current bi-annual release schedule of June and December for 2023.