A set of members all of which are members of another set (from set theory in mathematics).

Notes

• In SNOMED CT, the definition of subset applies to SNOMED CT components as follows:

  • A subset of SNOMED CT concepts is a set of concepts taken from a wider set of concepts.

  • A subset of SNOMED CT descriptions is a set of descriptions taken from a wider set of descriptions.

• The members of a subset can defined in one of two ways:
  • Extensionally, by enumeration, with a simple reference set as the standard distribution format.
  • Intensionally, using rules to determine inclusion, with a query reference set as the standard distribution format.

Examples

• A subset of SNOMED CT concepts from all of the concepts in a particular version of a SNOMED CT edition.

• A subset of SNOMED CT descriptions from all the descriptions in a particular version of a SNOMED CT edition.

Related Links

• Extensional subset definition

• Intensional subset definition

• Reference set

• Reference Sets Practical Guide, Subset
• Subset