The concept role relation is used to send code modifiers targeted for specific roles. Both modifiers and roles are defined by some coding systems and can only be used for coding systems that define those. For example, if SNOMED RT defines a concept "leg", a role relation "has-laterality", and another concept "left", the concept role relation allows to add the modifier "has-laterality: left" to a primary code "leg" to construct the meaning "left leg".
Note, that the use of modifiers is (as it always was) strictly governed by the code system used. In other words, it will not be permissible through this data type to use code modifiers with code systems that do not provide for modifiers (e.g. pre-coordinated systems, such as LOINC or ICD-10 PCS.) The rules of the modifier use must be governed by a code system (e.g., recent SNOMED RT revision, or GALEN.)
May invert the meaning of the role, in cases where the underlying code system does not provide reciprocal pairs of role names. For example, a code system may define the role relation "causes" besides the concepts "Streptococcus pneumoniae" and "Pneumonia". If that code system allows for its roles to be inverted, a user can construct the post-coordinated concept "Pneumococci pneumonia" through "Pneumonia - causes,inverted - Streptococcus pneumoniae."
Note that roles may only be inverted if the underlying coding systems allows such inversion. Notably, if a coding system defines roles in pairs, the appropriate role code (e.g. "caused-by") must be used rather than inversion.
The inversion_ind defaults to false.
Default: False
A code denoting the manner in which the value role relation value contributes to the meaning of a code phrase. For example, if SNOMED RT defines a concept "leg", a role relation "has-laterality", and another concept "left", the concept role relation allows to add the modifier "has-laterality: left" to a primary code "leg" to construct the meaning "left leg". In this example "has-laterality" is the Concept_role_relation.name.
Note that the role_relation.name is in itself a code value (CV) and must be defined by the code system that allows the use of such targeted modifiers. It is not allowed by a user to make up role names on an ad hoc basis.
The code related to the primary code of a code phrase through the role relation. For example, if SNOMED RT defines a concept "leg", a role relation "has-laterality", and another concept "left", the concept role relation allows to add the modifier "has-laterality: left" to a primary code "leg" to construct the meaning "left leg". In this example "left" is the Concept_role_relation.value.
This component is by itself of type Code_phrase, which allows modifiers to be themselves modified. Remember that all these modifiers can only be used if the code system defines them. It is not allowed to use any kind of modifiers for code systems that do not explicitly allow and regulate such use of modifiers.