Overview

Using the SNOMED CT subsets for COVID-19 data coding is dependent on a range of factors related to the local requirements and context of usage. Overall, the following three steps are important when planning and preparing the use of these subsets. In the following sections, we will provide information on each of these steps.

Identify Data Elements

Although the recording and use of COVID-19 data revolve around the same clinical scope, the requirements for content depends on the specific use case and the involved data items. Furthermore, different countries, regions, and hospitals may apply different practices which also result in differing requirements for content. Therefore, deciding which subsets to implement require you to clarify the scope of the content required, by answering questions such as:

• What will the subsets be used for?
  • Will it be used to capture new data in a clinical information system to support frontline service delivery?
  • Will it be used for disease surveillance?
  • Will it be used to integrate data from various sources?
  • Will it be used for retrospective analysis of data?
• Which data elements are required for the use case?
  • For data capture, what data needs to be collected to support the clinical process?
  • For disease surveillance, what parameters are required to monitor the disease progression?
  • For data integration, what data items will be shared or communicated?
  • For retrospective analysis of data, what are the available data items that are relevant to include for SNOMED CT analytics?
• What subsets are available and represent the data values of interest?
  • Are the subset members adequate for our needs?

Answering these questions will help in understanding which of the available subsets are relevant for your context, and it will also bring attention to potential content gaps or concepts which may be unnecessary for the specific scenario. Please note that the questions above are for inspiration, and there are likely to be additional questions to answer specific to your context.

Download Subsets

Subset Categories

The SNOMED CT COVID-19 subsets have been developed as a collection of concepts contributed from a range of Members that are considered to be potentially relevant to COVID-19 data coding. The subsets have been organized into the following 5 categories, determined by the data items which are likely to be recorded together. 

• Provider and Facility Details (PRF)

• Patient Demographics (PAT)

• Clinical Assessment (ASS)

• Tests and Investigations (INV)

• Prevention, Treatment, and Education (PTE)

Please follow the links in the lists above for detailed information on the specific subsets within each category.

Reference Set Tool

The SNOMED CT COVID-19 subsets are made available via the SNOMED International Reference set and translation tool, which can be accessed via this link: https://refset.ihtsdotools.org/

The subsets are placed in the 'COVID-19 subsets' project and are named according to the naming convention which is presented below. 

Subset Types

Some of the subsets are developed intensionally and others are developed extensionally. Please refer to the Practical Guide to Reference Sets, section 2.1.1. Subset Definitions for detailed information on this topic. 

For the subsets that have been extensionally defined, we provide two versions:

• One version which only includes the members listed 
• One version which includes the members listed, and the descendants of each of these members. This version supports the collection of more specific values where these are available.

Naming Convention

The reference sets have been named using a naming convention which follows the general categories of subsets.

Please see the examples of subset naming in the table below.

Review and Adapt

Prior to deployment, the subsets should be carefully reviewed and adapted to meet national or local requirements. As the subsets represent collections of concepts contributed from a range of SNOMED International Members, it is important to review the subset members to identify concepts that are not useful to the local concepts, and potentially identify meanings that are missing from the set, and should thus be added.

Additionally, it is important to ensure that the concepts included in the subsets are contained in the SNOMED CT Edition which the system uses. Checking this involves reviewing the effective time of the subset members and compare this to the version of the Edition you are using. The effective time of each subset member is shown in the tables.

Unpublished Content

Please note that the guide may include unpublished content, that should not be used until it has been published. An example of such member is the concept  882784691000119100 | Pneumonia caused by severe acute respiratory syndrome coronavirus 2 (disorder)|  in the CV19-ASS-Complications subset. This concept will be added in the July 2020 version of the International Edition. Although they are not yet available in the downloadable version of the subset, they are referenced in the subset tables of this guide to bring the upcoming additions to your attention and assist with planning.

Extension Content

In response to an immediate need for COVID-19-specific concepts, various Member countries have developed concepts within their national SNOMED CT Extensions. These extension concepts are documented in this guide and may be used as an inspiration to other Members. All though, please note that the extension concepts for COVID-19 are not included in the International Edition, and any implementers must only use the extension concepts available within the Edition they deploy. 

The extension concepts are not available in the Reference Set tool.

Feedback

We welcome any comments, feedback, and suggestions.