It should be noted that the Read Coded Clinical Terms are scheduled for a staged withdrawal commencing April 2016.
The Read Coded Clinical Terms are a comprehensive computerised coded thesaurus for use by clinicians. They are available in two main formats, known as Version 2 and Clinical Terms Version 3 (CTV3). They are designed for use in the electronic health care record. Clinical Terms Version 3 (CTV3) of the Read Codes is a "Superset" of all the codes from the earlier versions.
Read Coded Clinical Terms are not acceptable directly for coding Hospital Episode Statistics which are extracted from the Admitted Patient Care Commissioning Data Sets. Version 2 and Clinical Terms Version 3 (CTV3) of the Read Codes contain mapping tables which can be used to generate ICD-10 and OPCS-4 codes.