Concept Item

A specialised data structure containing data representing a concept. An identifier for the concept is mandatory and it may, optionally, provide information such as name, definition, relationships, etc. A concept defined by a Concept Item is identified by a {scheme alias, code} pair. The reverse relationship does not necessarily hold. In other words, there is no requirement that each {scheme alias, code} pair has a corresponding Concept Item. See also: representation of a Concept Item.