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United Kingdom modification of ICD-10 (5th Edition). Maintained by NHS England. Used for clinical coding across the National Health Service, with extensions for UK-specific clinical concepts.

Overview

  • While the international version of ICD-10 has 14,000 codes, the UK modifications has around 18,000 codes covering diseases, symptoms, injuries, and health encounters
  • Alphanumeric codes: 4–6 characters. If a code only has three characters, one must add an “X”.
  • Only conditions that affect patient care should be coded.
  • The rules for ICD-10 coding is different for inpatient and outpatient settings. We, therefore, require the user to specify the setting.

Encounter type

Encounter type is required. ICD-10 coding guidelines differ significantly between inpatient and outpatient settings. For instance, in the outpatient setting, one should only code established diagnoses. In the inpatient setting, one should also include all diagnoses that are uncertain, even those that are ruled out. Use icd10int-inpatient for inpatient cases and icd10-outpatient for outpatient cases. The correct guideline set is applied automatically based on the suffix.

Known issues

In England, there are certain secondary codes that one should always code, even if they do not directly impact patient care during the encounter. We have not implemented this list yet.
We have only evaluated this implementation on data from a neurology department. This may not generalize to other specialties and hospitals. We appriciate feedback if you encounter any issues.