The set of elements that are not in a specified set.
In set theory, the complement of set ** A** refers to all elements not in set ** A**.
In SNOMED CT, the complement of a _subset _of concepts consists of all concepts that are not in that subset.
The following expression constraint language defines the set of concepts that are subtypes of that are also part of the complement of the . The "MINUS" instruction excludes members of the reference set, so only concepts that are part of the complement of that set are included.
< MINUS ^
Related Links
Wikipedia