5.2. SCTID Representation

Each SCTID (data type) identifies aThe identifier itself does not contain information related to the meaning of aorThis means it is not possible to infer anything about the meaning of afrom the numeric value of the identifier or from the sequence of digits in that form of the identifer. The meaning of acan be determined fromto otherand from associatedthat include human readable terms.

The SCTID 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.

  • Theis 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-digitdistinguishes the identifiers of different component types and prevents the same identifier from being allocated to both aand aAs a result, when an SCTID is read from a record or other resource, it is possible to determine whether it represents aaor abefore 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 whichare reserved for an organization which is permitted to issue any valid identifiers within the allocated partitions. The short format approach does not require a specificand is only applicable to components originated and maintained by theas part of theof

    • Long format in which thevalue indicates that a separateis required to distinguish between components originated as part of ancreated 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