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ItemsProposed improvement

Planned Release date

(*this is provisional only and is subject to change)


COVID-19 Content Changes - Interim Release March 2020 (and subsequently in the July 2020 International Edition Release)

An INTERIM International Edition Release has been created as part of the ongoing global effort to tackle the Coronavirus outbreak and includes the updated Coronavirus descriptions for Members and implementers.

The full International Edition Release package containing changes to the content detailed in the news item ( under the following conditions:

  1. Following SNOMED International's critical incident policy, there will NOT be a recall of the January release, simply an update in response to international renaming, to ensure that SNOMED CT is current when assisting with the global Coronavirus effort.
  2. Implementers are encouraged to update to the new edition, however, they are NOT obliged to do so as the concept modelling and identifiers are not being modified.
  3. The entirety of these changes will also be incorporated into the upcoming July 2020 International Edition Release.

A set of new components have been added for the March 2020 Interim release:

    • 840534001   3950925017 COVID-19 vaccination 
    • 840544004   3950926016 Suspected COVID-19 
    • 840535000   3947177019 Antibody to severe acute respiratory syndrome coronavirus 2 (substance) 
    • 840535000   3947178012 Antibody to severe acute respiratory syndrome coronavirus 2 
    • 840535000   3947179016 Antibody to SARS-CoV-2 
    • 840536004   3947180018 Antigen of severe acute respiratory syndrome coronavirus 2 (substance) 
    • 840536004   3947181019 Antigen of severe acute respiratory syndrome coronavirus 2 
    • 840536004   3947182014 Antigen of SARS-CoV-2 
    • 840539006   3947183016 Disease caused by severe acute respiratory syndrome coronavirus 2 (disorder) 
    • 840539006   3947184010 Disease caused by severe acute respiratory syndrome coronavirus 2 
    • 840539006   3947185011 COVID-19 
    • 840546002   3947186012 Exposure to severe acute respiratory syndrome coronavirus 2 (event) 
    • 840546002   3947187015 Exposure to SARS-CoV-2 
    • 840546002   3947188013 Exposure to severe acute respiratory syndrome coronavirus 2 
    • 840533007   3947189017 Severe acute respiratory syndrome coronavirus 2 (organism) 
    • 840533007   3947190014 SARS-CoV-2 
    • 840533007   3947191013 Severe acute respiratory syndrome coronavirus 2
    • 840534001   3947192018 Severe acute respiratory syndrome coronavirus 2 vaccination (procedure) 
    • 840534001   3947193011 SARS-CoV-2 vaccination 
    • 840534001   3947194017 Severe acute respiratory syndrome coronavirus 2 vaccination 
    • 840544004   3947195016 Suspected disease caused by SARS-CoV-2 
    • 840544004   3947196015 Suspected disease caused by severe acute respiratory coronavirus 2 
    • 840544004   3947197012 Suspected disease caused by severe acute respiratory coronavirus 2 (situation) 

March 2020 Interim International Release


July 2020 International Edition Release


July 2020 International Edition Release format

The current plan is to publish the formal July 2020 International Edition with the March 2020 Interim release as the official "previous published release". 

This means that all COVID-19 content published in the March 2020 release will be present in both July 2020 Snapshot and Full files, with an effectiveTime of 20200309. The Delta files will be relative to March 2020, containing only new content from the July 2020 editing cycle, and will not duplicate the Delta file content from the March 2020 release.

  1. For those users who consumed the March 2020 Interim Release:
    1. It causes no issues for these users who want to use either the Full, Snapshot or Delta to update to July 2020.

  2. For those users who did NOT consume the March 2020 Interim Release:
    1. It may require some workarounds only for those users who want to use the Delta files, as they will not see the new Coronavirus content from March 2020. 
    2. They should therefore use one of the following methods to update:
      1. The best approach is to first apply the March 2020 Interim Release Delta files, and after that apply the July 2020 Release Delta files.
      2. Use the Snapshot files to update to July 2020 - this approach will also be supported going forward, for all future releases (even continuous delivery)
      3. Use a new Rollup Delta package that we will publish alongside the July 2020 Release:
        1. This July 2020 Rollup Delta package would be a separate resource with clear documentation.  It would include all changes since January 2020, with the actual, official effectiveTime. Therefore all of the new Corona content would have an effectiveTime of 20200309. The rest of the content will have an effectiveTime of 20200731.

        2. This rollup package would include instructions on how to cope with multiple effectiveTimes (per componentID), as this will be a necessary feature of rollup Delta files) - for example if a concept has been added in March 2020, and then inactivated in July 2020, both records will exist in the same Delta file for this rollup period.

        3. We may also use this Rollup package as an opportunity to trial the new proposal for the Delta file naming conventions - containing the effectiveTime of BOTH the current Delta, and also the release that the Delta is taken from - for example, if a Delta is from Jan 2020 to March 2020:

            1.  sct2_Concept_Delta_INT_20200131_20200309.txt 

  3. This proposal ensures that both deltas are consistent, and this therefore a) preserves RF2 protocols, and b) pushes forward the prep for continuous delivery.


July 2020 International Edition Release

Browse Content Changes for the July 2020 Release

The daily build is available to review changes made to content for the July 2020 release

Forthcoming concept inactivations, new concepts and changes to existing concepts can be reviewed using the tab 'Daily build.'

July 2020 International Release

Implementation of the new anatomy concept model

The completion of the revision of hierarchical relationships provides stable anatomy content and improves the quality of classification results in other hierarchies.

Over forthcoming releases, the plan is to implement the new anatomy concept model and release the changes in January 2021. There are almost 35,000 anatomy concepts and they will be modeled by different types of 'part of' relationships. The new model will enable us to automatically generate hierarchies to further improve quality and consistency. 

Information about the work completed in previous release for revision of IS_A relationships can be viewed here:

July 2020 International Release and future releases


Revision of the cell hierarchy

Over forthcoming releases, descendants of 4421005 |Cell structure (cell structure)| will be updated according to the SEP model.

SEP description patterns will be applied to the existing content. Descendants of 362837007 |Entire cell (cell)| will be updated to include the word ‘entire’ in all descriptions.

The semantic tag ‘(cell)’ will be changed to ‘(cell structure)’. Descriptions for the rest of the concepts will be updated to include the word ‘structure’. 

This modeling improvement will address the missing relationship between structure and entire concepts. 

Please contact with any inquiries or to submit feedback.

July 2020 International Release and future releases.


MRCM Changes

Please see:

MRCM changes for the July 2020 release

July 2020 International Release

Quality Initiative

Information about the project can found here - Quality Initiative - Progress

Note: There are changes to the Service Level Agreement for the CRS as a result of the Quality Initiative:

July 2020 International Release

Top level groupers/Allergen classes in substance hierarchy

Based on recommendation by the Allergies CRG, deprecation of top level groupers/Allergen classes in substance hierarchy, which has been partially done for Jan 2019 release, will be completed for July 2020 release.

Changes to Subtypes of 419199007 |Allergy to substance (finding)

As part of the QI project review of the 419199007 |Allergy to substance (finding)| sub-hierarchy and per the Allergies CRG recommendation, the concepts in this sub-hierarchy that represent allergy to "role groupers" and "Structure + role groupers" will be inactivated starting from the July 2020 release.

A few examples of these concepts are provided below:

    • 294450008 Allergy to anthelmintic agent (finding)
    • 294461000 Allergy to antibacterial drug (finding)
    • 294869008 Allergy to anticoagulant (finding)
    • 293857007 Allergy to anticonvulsant (finding)
    • 294263000 Allergy to antidote (finding)
    • 294340008 Allergy to antifungal agent (finding)
    • 294616009 Allergy to antileprotic drug (finding)
    • 294387001 Allergy to antimalarial agent (finding)
    • 294605002 Allergy to antimycobacterial agent (finding)
    • 293739003 Allergy to antineoplastic agent (finding)
    • 293863003 Allergy to barbiturate antiepileptic (finding)
    • 294430009 Allergy to biguanide disinfectant (finding)
    • 294603009 Allergy to hydroxyquinoline antiprotozoal (finding)
    • 294991000  Allergy to thiazide diuretic (finding)
    • 293757002  Allergy to triazene antineoplastic (finding)
July 2020 International Release and future releases.

Content Improvements in the Substance and Product Hierarchies

Please see briefing notes here Drugs Project

Please contact with any inquiries.

July 2020 International Release

Content Improvements in the Physical object Hierarchy

Please see briefing notes here

Please contact with any inquiries.

July 2020 International Release

Planned changes to 'Co-occurrent and due to' pattern

During the implementation of the new Description Logic features a conflict was uncovered between the modeling of 'Co-occurrent and due to' and General Concept Inclusions (GCIs). This has resulted in the need to reconsider the modeling of "Co-occurrent and due' and update the Editorial Guide for this area.

The plan is to update the Editorial Guide and all concepts that are currently modeled as 'Co-occurrent and due to' starting from the July 2019 release.

July 2020 International Release and future releases



Inactivation reason of LIMITED/WAS_A is not allowed for any new content inactivations after the July 2018 release. The WAS_A association refset has not been updated thereafter.

At the Editorial Advisory Group meeting in April 2019, agreement was reached to discontinue the maintenance of WAS_A relationships when inactivating concepts that have a historical association to an inactive concept. When changes are made to a historical relationship for a concept that was previously inactivated using WAS_A, effort will be made to assign a new historical relationship that facilitates traceability of the concept (e.g. DUPLICATE or AMBIGUOUS) as opposed to NON-CONFORMANCE TO EDITORIAL POLICY.

Existing WAS_A relationships will be inactivated in a future release once a plan for batch reassignment of historical relationships has been developed. Until then, SNOMED International will not continue to use or maintain WAS_A relationships.

July 2020 International Release and future releases

Changes for 'On examination' (O/E) and 'Complaining of' (C/O) concepts

  • Addition of any further required content
  • Inactivation of the O/E and C/O content (Batch change) for return to the UK.

Content being inactivated will use the reason - component moved elsewhere. 

Note: some concepts will not have a replacement concept as they are groupers. For example:
On examination - sign irregular (finding)
On examination - neurological reflex (finding)

Complete new content additions - July 2020 International Release

Content inactivation - January 2021 International Release


Traumatic Dislocation

Traumatic dislocation concepts are being remodeled according to the new representation using DUE TO "Traumatic event".

This work has been partially completed for the Jan 2020 release, resulting in the remaining subhierarchies moving from under "Traumatic dislocation of joint" to "Dislocation of joint". These remaining subhierarchies will be remodeled for the July 2020 release.

July 2020 International Release


Spinal Cord Syndrome

A new concept 840721004| Incomplete spinal cord syndrome (disorder) has been created as a grouper parent to the four major subtypes of this syndrome:

282785008 |Anterior cord syndrome (disorder)|

27982003|Brown-Séquard syndrome (disorder)|

282786009 |Posterior cord syndrome (disorder)|

282787000 |Central cord syndrome (disorder)|

In prior releases these syndromes had been modeled with an ASSOCIATED MORPHOLOGY = 19130008|Traumatic abnormality (morphologic abnormality)|; however, these syndromes may present due to non-traumatic etiologies such as space filling lesions (tumors, etc.) or vascular compromise (occlusions, ruptures, etc.).

These syndromes have been remodeled with ASSOCIATED MORPHOLOGY = 52988006|Lesion (morphologic abnormality)|.

Incomplete cord syndromes with a traumatic cause have been remodeled to specifically represent 773760007 |Traumatic event (event)| as the DUE TO value as well as any other relationships to describe associated disorders (e.g. fractures or dislocations).

July 2020 International Release

Planned changes to Implantation and Insertion procedures

Work commenced on content tracker IHTSDO-175 IHTSDO-175 - Getting issue details... STATUS

Ongoing structural changes for the Procedure concepts related to the content tracker:

July 2020 International Release


Other Occupations

Concepts representing "other" occupations e.g. 79445009 |Other clerk (occupation)| have been inactivated for the July 2020 release as these represent classification constructs.

July 2020 International Release

Replacement of the Stated Relationship files with the new OWL Axiom refset files

A set of documentations has been developed to support the Logic Profile Enhancements. 

For any questions, please contact SNOMED International at with “OWL Axiom refset files implementation question” in the subject line. 


  1. Will you add the Device content improvement aas per the briefing note published on this page: Member Exchange?

    1. The update has been added, Best wishes, Maria