SNOMED CT® Release Format 1 (RF1) Guide - ihtsdo

In addition, the ReferencedId field may also refer to a Concept when ComponentId refers to an inactive
Description and ReferenceType = 7 (Refers to Concept).This use of the References Table permits a Description
to be made inactive without having to retire its Concept. In such a case, the References Table indicates a
Concept which is correctly described by the Term of the inactive Description.
3.2.7.1.4. Historical relationships
Historical relationships link Inactive Concepts to the overall semantic structure of SNOMED CT. These
specialized Relationships should be used to map legacy data into the current subtype hierarchy of SNOMED
CT :
• An "erroneous" Concept is related to the corrected Concept that replaces it by a | REPLACED BY
|Relationship.
• A "duplicate" Concept is related to the Concept that it was found to duplicate by a | SAME AS |Relationship.
• An "ambiguous" Concept is related to the Concept (s) that represent its possible disambiguated meanings
by one or more | MAY BE A | Relationships.
• A Concept that has the status "Moved Elsewhere" or "Pending Move" is related to a Namespace Concept
by a | MOVED TO |Relationship. This identifies the namespace to which the Concept has been moved
or will be moved.
• A Concept that replaces a Concept moved from another namespace has a | MOVED FROM |Relationship
referring to the original Concept in its original namespace:
• If the Extension from which a Concept originated is not installed the target Concept will not be available.
This is not an error and can be safely ignored. The information in the Relationship is only of interest
to users of the original Concept.
• If the Concept has been moved to the SNOMED CT core namespace the | MOVED FROM |Relationship
should be maintained in the originating Extension.
3.2.7.2. Component History Rules
These are the rules used to create the Component History Table when components are added or changed.
components are never removed, but their status may change from active to inactive. Components that have
become inactive may sometimes subsequently have their status restored to active.
Special considerations for the SNOMED CT First Release are described in the last subsection.
3.2.7.2.1. Adding a Component
A newly added component is distributed as:
1. A row in the Component History Table with:
a. ChangeType value Added;
b. ComponentIdreferring to the new component;
c. Status value for the component (usually Current).
.
2. A row in the appropriate distribution table for the new component.
3.2.7.2.2. Changing the status of a Component
All SNOMED CT Components have an active or inactive Status.
When the Status of a component is changed, this is distributed as:
1. A row in the Component History Table with:
a. ChangeType value Status Change;
b. ComponentId referring to the changed component;
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