SNOMED CT expression

A structured combination of one or more concept identifiers that represents an idea.

An expression containing a single concept identifier is referred to as a precoordinated expression. An expression that contains two or more concept identifiers is a postcoordinated expression.
The syntax used to represent SNOMED CT expressions is called the SNOMED CT compositional grammar and is formally defined in the Compositional Grammar - Specification and Guide.
The concept identifiers in a postcoordinated expression are related to one another in accordance with rules expressed in the SNOMED CT Concept Model. These rules allow an expression to refine the meaning of a concept by applying more specific values to particular attributes of a more general concept.

The expression 284196006 |:363698007=770850006| represents a burn to the skin of the left index finger.
An expression can also include the terms related to each of the identified concepts as shown below:

284196006 |burn of skin| : 363698007 |finding site| = 770850006 |Skin structure of left index finger|

Alternatives