5.2. SCTID Representation

Each SCTID (data type) identifies a The identifier itself does not contain information related to the meaning of a or This means it is not possible to infer anything about the meaning of a from the numeric value of the identifier or from the sequence of digits in that form of the identifer. The meaning of a can be determined from to other and from associated that include human readable terms.

The SCTID (data type) does however have a structure which includes valuable information about the nature and source of the identified component and the validity of the identifier. This structure supports the following features:

• validation of the identifier.

  • The is the final digit in the decimal rendering of the identifier. This can be checked to minimize errors from transcription or incomplete copy-paste actions.

• Partitioning between identifiers for different types of

  • 
    A two-digit distinguishes the identifiers of different component types and prevents the same identifier from being allocated to both a and a As a result, when an SCTID (data type) is read from a record or other resource, it is possible to determine whether it represents a a or a before searching for the identified component.

• Namespaces to separate component identifiers originated by different organizations. 

  • Organizations are only permitted to issue identifiers which fall within a specified namespace of potential identifier values. This prevents collisions between identifiers issues by different organizations which would otherwise result in ambiguity and errors when sharing data.

  • There are two formats used for representing namespaces. 

    • Short format in which are reserved for an organization which is permitted to issue any valid identifiers within the allocated partitions. The short format approach does not require a specific and is only applicable to components originated and maintained by the as part of the of

    • Long format in which the value indicates that a separate is required to distinguish between components originated as part of an created by an appropriately authorized organization .

Figure 1. SCTID Short Format - Applicable to components originating from the International Release

Figure 2. SCTID Long Format - Applicable to components originating from a SNOMED CT Extension