Terminology and Classifications


National standards for recording and categorising information to support care delivery, statistical analysis, research and the reimbursement of health and care providers.

Top tasks

Work together and share on Delen
Use our Delen site to reach product documents, databases and tools. Access latest news, developments, opportunities and publications, plus education, training and exam information. Search the Resource Library for specific items, like the Coding Clinic.

Download e-learning, technical files and documentation
From our TRUD download website, which allows NHS Digital to license and distribute reference data.

NCCQ UK 2017 registration forms and study guidelines
The deadline for the National Clinical Coding UK Qualification exam on 26 September 2017 is 30 June.

Request changes
Use the request submission portal to request changes to Clinical Terms Version 3 (CTV3), NICIP, OPCS and SNOMED CT.

SNOMED CT webinars
Select dates and register your place now.

Further information

  1. Clinical Classifications

    OPCS-4 and ICD-10 are clinical classifications standards. Both are mandated nationally for use across the NHS and consist of groupings of concepts (codes), plus definitions and business rules for their use.

  2. Read Codes

    Read Codes are a coded thesaurus of clinical terms. There are two versions: version 2 (v2) and version 3 (CTV3 or v3).


    SNOMED CT is a structured clinical vocabulary for use in an electronic health record. It is the most comprehensive and precise clinical health terminology product in the world.