1. Introduction

The 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^®) maintains the SNOMED CT technical design, the content architecture, the SNOMED CT content (including the concepts table, the descriptions table, the relationships table, a history table and mappings), and related technical documentation. 

This document is intended to give a brief background to the Test/Review Protocol used on the SNOMED CT International/ICH (International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use) work through the EU funded WEB RADR 2 project and the resulting Release package and the resulting SNOMED CT/MedDRA maps, which are being published as an Alpha release at this time with intention to publish a production release in April 2021.  It is not a detailed technical document of SNOMED CT, MedDRA or the SNOMED CT International/ MedDRA release. Nor does it seek to provide an editorial policy for this content though does provide details of the Mapping conventions applied.

This ALPHA release package is distributed for evaluation purposes only.  It must not be used in production clinical systems or in clinical settings, or distributed to Affiliate Licensees or any third parties.   

2. Audience for this document

This document should be read by all those (SNOMED International National Release Centers, vendors of electronic health records, terminology developers, Regulators and Pharmaceutical Industry) with an interest in the usage of this content in SNOMED CT and its linkage with MedDRA i.e. the SNOMED CT to MedDRA and MedDRA to SNOMED CT maps based on a priority set of MedDRA. 

3. Background

In 2018, SNOMED International and ICH joined the WEB-RADR 2 project, funded by Innovative Medicines Initiative (IMI). SNOMED International and ICH lead the effort to develop 2 maps between SNOMED CT and MedDRA. A specific work package was devoted to this purpose and included participants from regulatory authorities and industry as well as SNOMED International and MedDRA MSSO. The project delivered the following:

• 2 maps (MedDRA to SNOMED CT and SNOMED CT to MedDRA) of frequently used pharmacovigilance MedDRA terms that were identified from databases from the UK’s Medicines & Healthcare products Regulatory Agency (MHRA) and the European Medicines Agency (EMA). This subset represents the high value terms to support interoperability between the terminologies.
• A set of Mapping conventions which were drafted as part of a pilot set and updated for the main body of work.
• A small number of content additions to SNOMED CT in support of the MedDRA high value terms as defined by scope and editorial rules of SNOMED CT.

The Use cases of the project were defined as:

SNOMED CT to MedDRA map:

Key pharmacovigilance concepts when coded in SNOMED CT in an electronic health record could be converted to MedDRA for the purpose of adverse event reporting to regulatory authorities or for the purposes of epidemiological research. 

The mapping work was undertaken using dual independent review by mappers who were Consortium members of the WEB RADR 2 project and experts in either SNOMED CT or MedDRA. Quality Assurance, based on the mapping conventions, was managed as part of the process by SNOMED International and MedDRA MSSO (on behalf of ICH) and technical assurance reports provided weekly using the Mapping tool used by all participants. A big thank you is offered to all contributors to the Maps. The Mapping Conventions used are provided for information as part of this package.

In parallel to the mapping work, the operational aspects have been worked on to agree activities and processes to enable the 2 Maps to move in to Production in April 2021 and from there to be maintained and updated according to changes within the 2 terminologies and Use Case based requirements for additions to the Maps - thus meeting one of the key requirements of IMI to produce products in the project that are sustainable over time.

At this time, SNOMED International and ICH are seeking feedback on the Alpha version of the 2 Maps, and a Test/Review protocol has been produced as part of this package which indicates some of the areas on which feedback is invited. The Test/Review period ends on 30 September 2020, after which work will be undertaken to update the Maps in line with January 2021 SNOMED CT International Release and MedDRA September 2020 release. A report of the feedback will be made available. Please note that the Maps will NOT be extended beyond current scope for the Production release. The Production release in April 2021 will be available to licensed users of either SNOMED CT of MedDRA.

MedDRA to SNOMED CT map:

Clinical care decision support: Terms coded in MedDRA representing adverse events, warnings, and other regulatory information in product labeling could be converted into SNOMED CT so that the information is integrated into the electronic health record or decision support system to be visible to healthcare professionals when prescribing, dispensing, or administering the product to patients.

As part of the WEB-RADR 2 project, funded by Innovative Medicines Initiative (IMI), ICH and SNOMED International lead the effort to develop maps between SNOMED CT and MedDRA. A specific work package was devoted to this purpose and included participants from regulatory authorities and industry as well as the standards development organizations.

The work package developed a set of maps (MedDRA to SNOMED CT and SNOMED CT to MedDRA) derived from frequently used key pharmacovigilance MedDRA terms that were identified from databases from the UK’s Medicines & Healthcare products Regulatory Agency (MHRA) and the European Medicines Agency (EMA). This subset represents the high value terms to support interoperability between the terminologies and includes terms used for adverse events, medical history, and indications. For further details, please refer to the Mapping Conventions document included in the Alpha Test/Review package.

The Maps represent a new product for both user communities and wider stakeholder groups. The Alpha test/review period is being used to collect feedback from users on the quality of the maps, both from a content and technical aspect, of the maps. In addition, feedback on the maps for specific use cases will be collected. The maps will not be revised during this test period. 

This period is intended to signal to both SNOMED CT and MedDRA user communities and wider stakeholders the availability of these new products and make any necessary updates ahead of the first production release based on the feedback. 

If you have any questions, please contact the MSSO Help Desk  (mssohelp@meddra.org) or SNOMED International (info@snomed.org)

4. Use Cases of the Maps 

A major goal of the WEB-RADR 2 project was to use the enhanced functionality of the mobile application to facilitate exchange of data between regulatory databases (which use MedDRA) and healthcare databases/electronic health records (which use SNOMED CT).

4.1.1. MedDRA to SNOMED CT map:

Example of a use case for clinical care decision support: Terms coded in MedDRA representing adverse events, warnings, and other regulatory information in product labeling could be converted into SNOMED CT so that the information is integrated into the electronic health record or decision support system to be visible to healthcare professionals when prescribing, dispensing, or administering the product to patients.

4.1.2. SNOMED CT to MedDRA map:

In one example of a use case, key pharmacovigilance concepts when coded in SNOMED CT in an electronic health record could be converted to MedDRA for the purpose of adverse event reporting to regulatory authorities or for the purposes of epidemiological research.

Note: As a part of this test/review phase, we request that you provide information on your use case so we can understand how the maps will be used. 

5. Testers/Reviewers

• Regulatory and industry users, vendors, clinical users and SNOMED International member countries

• Can be MedDRA or SNOMED CT subscribers (or both)

• Must have access to SNOMED CT coded data

• Must have defined use cases as described above 

6. Timeline for test/review

The alpha test/Review period will run from 1 April 2020 to 30 September 2020.

Upon completion, SNOMED International and ICH will review the feedback and implement updates/changes agreed by both organizations. 

The Production version of the maps will be made available to licensed SNOMED CT or MedDRA Users in April 2021, and will be based on the January 2021 version of SNOMED CT and the September 2020 version of MedDRA. It is planned that the maps will be released annually in April. 

7. Map details

Both Maps (MedDRA to SNOMED CT and SNOMED CT to MedDRA) for the alpha test/review are based on:

• MedDRA Version 21.1 (released September 2018)

• SNOMED CT January 2019 International edition

They are available in spreadsheet and RF2 formats; the content is identical in both formats.

7.1. MedDRA to SNOMED CT map

6,374 LLTs mapped to SNOMED CT Fully Specified Names (FSNs)

Example below

7.2. SNOMED CT to MedDRA map

3,684 FSNs mapped to MedDRA LLTs

Example below 

Note that the MedDRA to SNOMED CT map is larger than the SNOMED CT to MedDRA map because in the former, more than one LLT can map to an FSN.

For example, both UK and US spelling variants in MedDRA map to a single FSN which uses the US spelling. In the other direction, the US spelling FSN maps to a single US spelling MedDRA LLT.

• LLT Oedema and LLT Edema map to FSN Edema (2:1 cardinality)

• FSN Edema maps to LLT Edema (1:1 cardinality)

In another example, more than one synonymous LLTs in MedDRA map to a single FSN. 

Please refer to the MedDRA to SNOMED CT and SNOMED CT to MedDRA Mapping Conventions document here: SNOMED CT MedDRA Simple Map package ALPHA Mapping Conventions - April 2020 for details of the principles applied in creating the maps from the initial data set.