description logic classifier

A software tool that applies the rules of description logic to a set of axioms to infer additional relationships between concepts.

Notes

• SNOMED CT concept definitions are processed by a description logic classifier to generate inferred subtype hierarchies.

• SNOMED CT expressions can also be processed by a description logic classifier to make inferences that enable more complete and precise selective retrieval to support analytics.

Alternatives

• Classifier

description logic

A representation of semantic knowledge that allows formal reasoning to be applied based on axioms.

Notes

• Description logic definitions of SNOMED CT concepts are represented in two ways, as: * OWL Functional Syntax in an OWL Expression Reference Set * Defining relationships in the Relationship File.

• The formal rules of description logic can be applied to concept definitions by software tools (description logic classifiers) to interpret the meaning of concepts. This enables confirmation of the logical integrity of the terminology, and can also be used to support meaning-based retrieval from records containing SNOMED CT expressions or concepts.

Alternatives

• DL

This is an abbreviation for SNOMED CT description.

An association between a human-readable phrase (term) and a particular SNOMED CT concept.

• Each description is represented by a separate row in the Description File.

• Each description has a unique identifier and connects a concept with a term of a specified description type. All concepts have descriptions with description types fully specified name and synonym. Other description type can be defined and may be applied to some concepts.

description type

An indication of the intended use of a term of a SNOMED CT description when applied to the associated concept.

Notes

• The description type is represented by the value of the description.typeId attribute.

• Permitted values include the following (other types may be defined in future):

| synonym * A word or phrase that expresses the meaning of a SNOMED CT concept in a specified language. | textual definition * A narrative text explanation of the meaning of a concept that may exceed the maximum permitted length for a fully specified name.

A SNOMED CT identifier that uniquely identifies a description.

A process that generates a set of logically consistent inferences by applying description logic rules to the stated view of concept definitions.

• Automatic classification