SNOMED CT The Irish National Release Centre


SNOMED CT Irish Edition Release

The Irish National Release Centre provides the release files, subsets, refsets, mappings and related documents for those using SNOMED CT Irish Edition within their systems

For further information go to our Strategic Programme SNOMED CT


Ireland became the 29th member of SNOMED International on 31st of  October 2016, SNOMED International is the organisation responsible for SNOMED CT (Systemised Nomenclature of Medicine for Clinical Terms) internationally.  SNOMED CT is internationally recognised as a robust terminology for healthcare.  This is hugely exciting for information standards and data quality for healthcare in Ireland. The adoption of SNOMED was recommended in the comprehensive HIQA report in May 2014. This initiative represents a real step in the right direction using an internationally recognised robust classification standard for healthcare in the continually evolving journey of data to information around Health information standards in Ireland to support eHealth.

  • Benefits populations
  • Benefits individual patients and clinicians
  • Supports evidence based healthcare

Why is this important?

Understanding the benefits of SNOMED CT  will inform key decisions and the development of strategies for adoption, implementation and use of this clinical terminology.

What is this?

SNOMED CT supports the development of comprehensive high-quality clinical content in health records. It provides a standardized way to represent clinical phrases captured by the clinician and enables automatic interpretation of these. SNOMED CT  is a clinically validated, semantically rich, controlled vocabulary that facilitates evolutionary growth in expressivity to meet emerging requirements.

Electronic Health Records

SNOMED CT  based clinical information benefits individual patients and clinicians as well as populations and it supports evidence based care.

The use of an Electronic Health Record  (EHR) improves communication and increases the availability of relevant information. If clinical information is stored in ways that allow meaning-based retrieval, the benefits are greatly increased. The added benefits range from increased opportunities for real time decision support to more accurate retrospective reporting for research and management.

SNOMED CT Enabled Health Records Benefit Individuals

SNOMED CT enabled clinical health records benefit individuals by:

  • Enabling relevant clinical information to be recorded using consistent, common representations during a consultation.
  • Enabling guideline and decision support systems to check the record and provide real-time advice, for example, through clinical alerts.
  • Supporting the sharing of appropriate information with others involved in delivering care to a patient through data capture that allows understanding and interpretation of the information in a common way by all providers.
  • Allowing accurate and comprehensive searches that identify patients who require follow-up or changes of treatment based on revised guidelines.
  • Removing language barriers ( SNOMED CT enables multilingual use).


SNOMED CT  enabled clinical health records benefit populations by:

  • Facilitating early identification of emerging health issues, monitoring of population health and responses to changing clinical practices.
  • Enabling accurate and targeted access to relevant information, reducing costly duplications and errors.
  • Enabling the delivery of relevant data to support clinical research and contribute evidence for future improvements in treatment.
  • Enhancing audits of care delivery with options for detailed analysis of clinical records to investigate outliers and exceptions.

 SNOMED Population benefits

SNOMED CT Enabled Health Records Support Evidence-Based Healthcare

  • SNOMED CT enabled health records inform evidence based health care decisions by:
  • Enabling links between clinical records and enhanced clinical guidelines and protocols.
  • Enhancing the quality of care experienced by individuals.
  • Reducing costs of inappropriate and duplicative testing and treatment.
  • Limiting the frequency and impact of adverse healthcare events.

Raising the cost-effectiveness and quality of care delivered to populations.

SNOMED CT Features


  • Is the most comprehensive, multilingual clinical healthcare terminology in the world.
  • Is a resource with comprehensive, scientifically validated clinical content.
  • Enables consistent, process able representation of clinical content in electronic health records.
  • Is mapped to other international standards.
  • Is already used in more than fifty countries.

When implemented in software applications, SNOMED CT can be used to represent clinically relevant information consistently, reliably and comprehensively as an integral part of producing electronic health information.

Implementation requires an understanding of the way that SNOMED CT  content is represented by components  and supported by reference sets  (Refsets).


Exploring SNOMED CT

While reading the guide, you may find it useful to explore the content of SNOMED CT . You can do this using one of a range of online browsers listed on our web site at Note that the listed browsers  are not endorsed by SNOMED International  and they should only be used to a get feel for the content and structure of the terminology. It is useful to experiment with several different browsers  as they vary in the way they present particular features of the terminology.


SNOMED CT Design and Development

SNOMED CT Components

SNOMED CT is a core clinical healthcare terminology that contains concepts with unique meanings and formal logic based definitions organized into hierarchies . SNOMED CT  content is represented using three types of components :

These components  are supplemented by reference sets , which provide additional flexible features and enable configuration of the terminology to address different requirements.


SNOMED CT concepts represent clinical thoughts, ranging from |abscess| to |zygote|. Every concept  has a unique numeric concept identifier . Within each hierarchy, concepts are organized from the general to the more detailed. This allows detailed clinical data to be recorded and later accessed or aggregated at a more general level.


SNOMED CT descriptions link appropriate human readable terms to concepts . A concept  can have several associated descriptions , each representing a synonym  that describes the same clinical concept. Each translation  of SNOMED CT  includes an additional set of descriptions , which link terms  in another language  to the same SNOMED CT concepts . Every description  has a unique numeric description identifier.


SNOMED CT relationships  link concepts to other concepts  whose meaning is related in some way. These relationships  provide formal definitions and other properties of the concept . One type of relationship is the |is a| relationship  which relates a concept to more general concepts . These |is a| relationships  define the hierarchy of SNOMED CT concepts.

For example, the concepts  |bacterial pneumonia| and |viral pneumonia| both have an |is a| relationship to |infective pneumonia| which has an |is a| relationship to the more general concept  |pneumonia|.

Other types of relationships  represent aspects of the meaning of a concept.

For example, the concept  |viral pneumonia| has a |causative agent| relationship to the concept |virus| and a |finding site| relationship to the concept  |lung|.

Every relationship  has a unique numeric relationshipidentifier.

Reference sets

Reference sets (Refsets) are a flexible standard approach used by SNOMED CT  to support a variety of requirements for customization and enhancement of SNOMED CT . These include the representation of subsets , language preferences for use of particular terms  and mapping  from or to other code systems. Every reference set  has a unique numeric concept identifier.

SNOMED CT Characteristics - Comprehensive, Scalable and Flexible

SNOMED CT has a broad coverage of health related topics. It can be used to describe a patient's medical history, the details of an orthopedic procedure, the spread of epidemics, and much more. At the same time, the terminology has an unmatched depth, which enables clinicians to record data at the appropriate level of granularity.

Specific applications tend to focus on a restricted set of SNOMED CT , such as concepts  related to ophthalmology. These subsets  can be used to present relevant parts of the terminology, depending on the clinical context and local requirements. This means for example, that a drop down list to select diagnoses in an electronic health record  in a mental health facility can be tailored to that setting. Similarly, subsets  can be defined for problem lists for physician specialties or to provide appropriate medication lists for nurses in community care.

When individual jurisdictions have needs beyond those that can be reflected in a global terminology, perhaps due to requirements in local legislation, they can develop local or national extensions . Thus, even though SNOMED CT  is global in scope, it can be adapted to each country's or areas requirements. SNOMED CT  maps work to provide explicit links to health related classifications and coding schemes in use around the world, e.g. statistical classifications  such as ICD-9-CM, ICD-10 , and ICD-O3 . Maps to or from several national code systems are also available from, or under development, by Members . Maps to or from clinical domain specific code systems are also maintained by specialty groups with which SNOMED International  has collaborative agreement. Maps facilitate reuse of SNOMED CT  based clinical data for other purposes, such as reimbursement or statistical reporting.


Supporting Different Languages

SNOMED CT  is a multinational, multilingual terminology. It has a built-in framework to manage different languages  and dialects . The International Release  includes a set of language independent concepts  and relationships . Today, SNOMED CT  is available in US English, UK English, Spanish, Danish and Swedish. Partial translations  into Canadian French, Lithuanian, and several other languages  are currently taking place, and further languagetranslations are being planned by Members. The basic objective of any SNOMED CTtranslation  is to provide accurate representations of SNOMED CT concepts  in a way that is understandable, usable, and safe. Translation must be concept  based. Translators need to analyse concepts based on the fully specified name  and take account of its position within the hierarchy , its descriptions , and its relationships  to other concepts . This enables a meaningful translation  of a concept  based on phrases that are well used and clearly understood in all countries. SNOMED International  maintains guidelines and other materials to support countries undertaking translations.

SNOMED CT Products and Services

Members  and organizations covered by the SNOMED CT Affiliate License  have access to a range of products and services, including:

  • SNOMED CT terminology files consisting of:
  • Concepts
  • Descriptions
  • Relationships
  • Derivative works that help in the uptake and use of SNOMED CT , including Reference Sets  that support:
  • Identification of subsets of SNOMED CT content
  • or dialect  preferences for use of particular  descriptions
  • Maps to other code systems and classifications
  • Other relevant metadata  to support use of SNOMED CTcomponents.
  • Implementation guidance for successful use of SNOMED CT  including:
  • Implementation guidance
  • Translation guidance
  • Editorial guidance for content development
  • Access to services supporting submission of requests for changes or additions to content and documentation.
  • Participation in the global SNOMED International  community through an electronic collaborative space and meeting of special interest groups.