Core Metadata Concept

Hierarchy	900000000000442005 \| Core metadata concept\|
Purpose	This concept is the supertype for metadata used directly by SNOMED CT components.
Concept Addition Rules	No new subtype children may be added in an extension. See tables below for concept addition rules for each of the subtypes of 900000000000442005 \| Core metadata concept\| .

Characteristic Type

Hierarchy	900000000000449001 \| Characteristic type\|
Purpose	This subhierarchy provides the values for Relationship.characteristicTypeId.
Examples	900000000000227009 \| Additional relationship\| 900000000000006009 \| Defining relationship\| 900000000000225001 \| Qualifying relationship\|
Concept Addition Rules	No new subtype descendants may be added in an extension.

Hierarchy	900000000000444006 \| Definition status\|
Purpose	This subhierarchy provides the values for Concept.definitionStatusId
Examples	900000000000073002 \| Defined\| 900000000000074008 \| Primitive\|
Concept Addition Rules	No new subtype descendants may be added in an extension.

Hierarchy	900000000000446008 \| Description type\|
Purpose	This subhierarchy provides the values for Description.typeId
Examples	900000000000550004 \| Definition\| 900000000000003001 \| Fully specified name\| 900000000000013009 \| Synonym\|
Concept Addition Rules	Additional types permitted provided these are additive and do not replace the synonym or fully specified name values
Concept Addition Uses Cases	Different lengths of text for different purposes Different formats for text including HTML Specialized usage of text for a specific purpose

Hierarchy	900000000000450001 \| Modifier\|
Purpose	This subhierarchy provides the values for Relationship.modifierId
Examples	900000000000452009 \| All\| 900000000000451002 \| Some\|
Concept Addition Rules	No new subtype descendants may be added in an extension.

Hierarchy	900000000000443000 \| Module\|
Purpose	This subhierarchy provides the concepts used to identify modules
Examples	900000000000207008 \| SNOMED CT core\| 900000000000012004 \| SNOMED CT model component\| 449081005 \| SNOMED CT Spanish edition module\| 449080006 \| SNOMED CT to ICD-10 rule-based mapping module\| 449079008 \| SNOMED CT to ICD-9CM equivalency mapping module\|
Concept Addition Rules	The addition of modules that form part of the extension is required. These new module concepts must either be direct children of 900000000000443000 \| Module\| or descendants of a child of 900000000000443000 \| Module\| that is owned by the same extension provider. It is not permitted to add modules as subtypes of modules maintained by another extension provider. Each module concept added within an extension must have an identifier that contains the extension's namespace identifier.
Concept Addition Uses Cases	The addition of at least one module concept is essential for all extensions. More than one module concept may be added to enable content to be organized into separate modules.