Q. What is SNOMED-CT and why do I need to know about it?

Most GPs will be familiar with the ICD-10 (International Classification of Disease) or ICPC-2 (International Classification of Primary Care) systems of classification. ICD started out in the 19th century as a system of classification for cause of death and is considered by many to be less than ideal in the GP setting. ICPC in contrast was designed for primary care in the 1980s but is often felt to be too limited in its scope. ICPC-2 is used in all GPIT-accredited software
systems, often in conjunction with ICD-10, the latter being the coding sought on diagnoses for social welfare reports.

SNOMED CT (Systemised Nomenclature of Medicine for Clinical Terms) is another classification system which is important and may supersede ICPC and ICD. SNOMED CT is the most comprehensive multilingual clinical healthcare terminology in the world. The adoption of SNOMED was recommended in a comprehensive HIQA report in May 2014, and Ireland became the 29th member of SNOMED International on October 31, 2016. It is likely that SNOMED CT
will become the standard throughout the health service in Ireland.

Coding should not be an abstract concept for GPs and we should consider both its current and potential benefits.

• It makes it easier to identify key patient groups such as diabetics and asthmatics, helping us to optimise their clinical care
• Audit, training and indeed research are supported by the ability to quickly obtain high quality clinical information
• Clinical support systems may be developed using the clinical information in a patient record.

However, it is important to remember that coding should ideally take place as a background process when making entries to our computerised medical records. This may occur through the selection of pre-coded terms, or by the software offering suggestions in response to the GP typing.

SNOMED CT may take a while to grasp, but its coverage includes clinical findings, symptoms, diagnoses, procedures, body structures, organisms, pharmaceuticals and more. It is designed for use both in primary and secondary care and is driven by clinical requirements.

SNOMED CT is described as having three distinct components – concepts, descriptions and relationships

• The concept represents a 'clinical thought' and has a unique numeric identifier
• The description links human terms to concepts and allows for different descriptions of the same concept
• The relationship is used to link concepts, eg. a 'virus' may affect the 'upper respiratory tract' causing an 'infection'

To read more, visit www.snomed.org/snomed-ct

In the short term, this is unlikely to affect the majority of GPs, but it does have more medium-to long-term implications. With increasing linkage of primary and secondary care records via electronic referrals and discharges, the adoption of a single classification system for Ireland makes good clinical sense, and SNOMED CT seems to be the likely choice.

In the UK, the transition process is already underway to allow all GP software systems to adopt SNOMED CT. If introduced to Ireland we will be able to learn from this experience.