5.4.1.3 Management of Inactivated International Concepts within an Extension

When a concept from the International Edition is inactivated but still in use nationally, action is needed to resolve this. Inactivated concepts should generally not be used in production systems and should be replaced with active concepts, typically guided by historical associations. However, in some cases, circumstances may require continued use of an inactivated concept. This document provides guidance on the principles and considerations involved in managing such scenarios.

Can I reactivate inactivated international concepts in my extension?

The answer to this question is ‘sometimes’, but careful analysis is required before choosing to reactivate. Several factors need to be considered. In some cases, reactivation is strongly discouraged, while in others, it may be acceptable if handled correctly. Our overall advice is to approach reactivation cautiously, evaluating each case individually.

Before reactivating a concept, consider the following:

• Reason for Inactivation: If reactivation is discouraged for a specific reason, a new concept that reflects the intended meaning may be the best option.
• Type of Concept: The impact of reactivation varies by concept type. For example, reactivating an administrative concept inactivated due to being out of the scope of the International Edition, may be acceptable. However, reactivating a clinical concept inactivated due to ambiguity could compromise patient safety and should be avoided.
• Usage: What is the frequency of use? How will the inactivation impact users and systems? There needs to be a good clinical use case or business reason for reactivation. It may be used as an interim step whilst a more long-term solution is put into place and then the concept in question is inactivated again. If the concept is used locally or within a single country, reactivation may be possible. However, if it supports cross-border interoperability, reactivation is strongly discouraged. In such cases, creating a new concept in your extension is preferred, ensuring that any involved consumers can unambiguously interpret the meaning.

Please note that multiple extensions may choose to reactivate an inactivated concept, resulting in multiple versions with potentially conflicting interpretations or uses. Therefore, it is essential that these reactivated concepts are not used for cross-border interoperability.

Reason for inactivation

The table below summarizes the actions to take when considering reactivating an inactivated concept, depending on the reason for inactivation.

Reactivation in more than one extension module

An inactivated extension concept may be reactivated in more than one extension module, however prior to doing so consideration needs to be given to 

• The potential for the meaning of the concept to be understood differently in different jurisdictions.
• The potential for the use of the concept in more than one jurisdiction.

If the concept is reactivated in multiple extensions, one might assume that the meaning of the component is the same as the SCTID is the same.  If this component is then exchanged between jurisdictions, there is the possibility of inaccurate interpretation of meaning.

Examples:

• The January 2021 International Release included the bulk inactivation of “on examination <x> concepts. These concepts had come from the UK as part of CTV3 and were in high usage by UK GP’s. The UK NRC reactivated these concepts in bulk to prevent disruption to users. The concepts are now being reviewed and some are being inactivated within the UK extension. 
• In 2021, over 2000 concepts relating to breeds were inactivated from the international release and reactivated in the veterinary extension. Examples: 64158000 |Angora goat (organism)|, 62137007 |Labrador retriever (organism)|. 
• 51631009 |Ligation of major artery of extremity (procedure)| was inactivated as ambiguous for September 2023 release. This concept should not be reactivated in an extension due to the ambiguity of the term ‘major’ - no clear definition of this exists. 

Managing historical associations for a new concept

When creating a new concept to replace an inactivated concept, it’s helpful to establish a historical association between the inactivated international concept and the active extension concept. 

Historical associations are important because they form the backbone for maintaining continuity and traceability of clinical data when concepts are inactivated or replaced. These associations allow systems to link inactivated concepts to their appropriate replacements or related active concepts, ensuring that the integrity of historical data is preserved.

A key reason for establishing historical associations is to facilitate the querying of historical data using the Expression Constraint Language (ECL). ECL enables the retrieval of SNOMED CT concepts based on a range of criteria, including concepts with established historical associations. When a historical association is created between an inactivated concept and its replacement or related concept, history supplements enable users to include inactivated concepts in their queries. This ensures that historical clinical information remains accessible and interpretable, even as terminology evolves.

In most cases, historical associations will already exist between the inactivated concept and an active international concept. However, to ensure complete traceability, you should also create a historical association linking the inactivated concept to the new extension concept.

Please refer to the following pages to learn more about managing concept inactivation and historical associations:

• Editorial Guide: Concept Inactivation
• Reference Set Practical Guide: Managing Component Inactivation
• Expression Constraints Specification and Guide: History Supplements