1. Introduction

The HPO to SNOMED CT Map Release is the product of a joint project carried out under a collaboration agreement between XXXXXXXXXXXXXXXXXXXXXXXX and SNOMED International. The first release, in XXXXXXXXXXXXXXXXXX, was based on XXXXXXXXXXXXXXXXXX.  Work is now complete  between SNOMED CT and XXXXXXXXXXXXXXXXXX, taking into account the differences in structure and rules of each terminology. A maintenance and updating plan is now in place to ensure alignment is maintained overtime.

One of the key use cases for this standardised map is XXXXXXXXXXXXXXXXXX. Details are found in following links:

• ....
• ....
• ....

This document is intended to provide a brief description, background context and explanatory notes on the SNOMED International/XXXXXXXXXXXXXXXXXX collaborative work and the resulting HPO to SNOMED CT Map.   The map is being published as the Production release with the plan of publishing annually in XXXXXXXXXXXXXXXXXX.   This document is not intended to provide technical specifications about SNOMED CT or XXXXXXXXXXXXXXXXXX.   Editorial guidance for SNOMED CT content can be found in the SNOMED CT Editorial Guide.   Editorial guidance for XXXXXXXXXXXXXXXXXX can be found in XXXXXXXXXXXXXXXXXX

2. Audience

The audience for this document includes National Release Centers, vendors of electronic health records, terminology developers, researchers, genomics experts and individuals who wish to have an understanding of the content of the HPO to SNOMED CT Map.

3. Background

SNOMED International (then IHTSDO) and XXXXXXXXXXXXXXXXXX first started exploring opportunities for linking SNOMED CT and XXXXXXXXXXXXXXXXXX in XXXXXXXXXXXXXXXXXX because of the drivers to link between clinical data using SNOMED CT and the XXXXXXXXXXXXXXXXXX. As a consequence, an agreement was signed in XXXXXXXXXXXXXXXXXX and a priority set of XXXXXXXXXXXXXXXXXX was agreed. Since then, the two organisations have worked closely as follows to:

1. Undertake a gap analysis for the defined set.
2. Develop textual definitions for the XXXXXXXXXXXXXXXXXX.
3. Create new content in SNOMED CT.
4. Create a map between existing and new content in SNOMED CT and XXXXXXXXXXXXXXXXXX.
5. Ensure throughout the development period that new SNOMED CT content aligns with changes in XXXXXXXXXXXXXXXXXX.

XXXXXXXXXXXXXXXXXX new XXXXXXXXXXXXXXXXXX concepts were added to SNOMED CT as part of this collaboration and the resulting map product in XXXXXXXXXXXXXXXXXX contain XXXXXXXXXXXXXXXXXX SNOMED CT and XXXXXXXXXXXXXXXXXX concepts/terms. 

An updated Agreement was signed in XXXXXXXXXXXXXXXXXX signalling both organisations commitment to maintaining and updating the content and map. A further XXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXX entries were reviewed for inclusion in the map.

This XXXXXXXXXXXXXXXXXX 2023 release now represents an alignment between SNOMED CT and XXXXXXXXXXXXXXXXXX where in scope and a maintenance and updating process is being put in place to ensure this alignment is maintained as changes take place in both terminologies and the map updated accordingly.

4. Scope and Purpose of Collaborative Work

Under the terms of the Collaboration agreement between SNOMED International and XXXXXXXXXXXXXXXXXX, the Map will be issued annually by both SNOMED International in RF2 format and INSERM in spreadsheet format. Documented quality assurance processes will ensure that the content of both formats are the same and supporting materials are produced jointly. 

5. Design

5.1. Content Changes for 2023 ALPHA Release

The key changes made to content for the 2023 ALPHA Release:

1. Update to map for content that has been inactivated in SNOMED CT.
2. Removal of map from production release for entries that have been marked obsolete, deprecated or non-rare in XXXXXXXXXXXXXXXXXX.
3. Total New mapped concepts this release - XXXXXXXXXXXXXXXXXX
4. Total inactivated mapped entries this release - XXXXXXXXXXXXXXXXXX

5.2. Map

Decisions about maps between pre-existing content in SNOMED CT and XXXXXXXXXXXXXXXXXX, the creation of new content for SNOMED CT and also XXXXXXXXXXXXXXXXXX, and the validation of the map between SNOMED CT and XXXXXXXXXXXXXXXXXX were made by consensus between both organisations.

5.3. Version

The version of XXXXXXXXXXXXXXXXXX used is XXXXXXXXXXXXXXXXXX.  

The version of SNOMED CT used is the December 2022 International Release.

5.4. Source for Map

The source data is a subset of XXXXXXXXXXXXXXXXXX SNOMED CT concepts.

5.5. Direction of Map

The direction of the map is from HPO to SNOMED CT December 2022 International Release.

5.6. Cardinality of Map

The cardinality in the table is one-to-one, one SNOMED CT concept maps to one XXXXXXXXXXXXXXXXXX entry.

6. Obtaining the Release package

Access within SNOMED International member countries is provided by the Member National Release Centre in each country, via the relevant Member page. Affiliates of SNOMED International in non-member countries can access the map file through their Member Licensing and Distribution Service (MLDS) account. Please contact info@snomed.org for more information if required. 

The Map in spreadsheet form is available for download from the XXXXXXXXXXXXXXXXXX website:  

If you’re having any problems getting hold of the XXXXXXXXXXXXXXXXXX Map Package, please contact info@snomed.org.

Users of the map must comply with licensing arrangements for both SNOMED CT and XXXXXXXXXXXXXXXXXX.

7. Feedback

Feedback should be sent jointly to info@snomed.org and XXXXXXXXXXXXXXXXXX.

Feedback should include any issues relating to implementation, suggestions for future content inclusion or general comments regarding the map.

8. Technical Notes

8.1. RF2 package format

The RF2 package convention dictates that it contains all relevant files, regardless of whether or not there is content to be included in each particular release.  Therefore, the package contains a mixture of files which contain both header rows and content data, and also files that are intentionally left blank (including only a header record).  The reason that these files are not removed from the package is to draw a clear distinction between:

1. ...files that have been deprecated (and therefore removed from the package completely), due to the content no longer being relevant to RF2 in this or future releases, and 
2. ...files that just happen to contain no data in this particular release (and are therefore included in the package but left blank, with only a header record), but are still relevant to RF2, and could therefore potentially contain data in future releases.

This allows users to easily distinguish between files that have purposefully been removed or not, as otherwise if files in option 2 above were left out of the package it could be interpreted as an error, rather than an intentional lack of content in that release.