Equivalent Code Sequence Attribute
| Tag | (0008,0121) |
|---|---|
| Type | Optional (3) |
| Keyword | EquivalentCodeSequence |
| Value Multiplicity | 1 |
| Value Representation | Sequence (SQ) |
Codes that are considered equivalent by the creating system.
One or more Items are permitted in this Sequence.
See Section 8.9.
Section 8.9
8.9 Equivalent Code Sequence
The Equivalent Code Sequence (0008,0121) Attribute may optionally be used to convey different codes for the same concept.
Equivalence is defined as having the same or similar meaning, and requires that equivalent concepts do not include different aspects, properties, features, characteristics, or parameters.
Note
E.g., the SNOMED and FMA codes for a structure of the breast, (76752008, SCT, "Breast") and (57983, FMA, "Breast") would be considered equivalent. Neither would be equivalent to concepts that pre-coordinated other aspects such as laterality, e.g., (80248007, SCT, "Left breast"), or entire body organ, e.g., (181131000, SCT, "Entire breast").
Some scenarios in which it is helpful for the creating system to send equivalent codes include:
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when different representations of the same concept are present in a standard coding scheme, such as the SNOMED-CT and SNOMED-RT and CTV3 style identifiers,
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when the same concept is present in different standard coding schemes, but considered by the creating system to be synonymous, such as anatomical concepts from SNOMED and FMA, and
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when the same concept is present in a local as well as a standard coding scheme, but considered by the creating system to be synonymous, such as a local private procedure code and the same concept in LOINC or SNOMED or RADLEX.
The Table 8.8-1b may be used to identify a Context Group from which the codes were selected, such as for a particular cross-institutional, cross-application context for trials, research and knowledge-based applications.