1 of 1

SCTID Constraints

The permissible value for the SCTIDs are limited by the following rules:

Only positive integer values that are greater than 10⁵ and less than 10¹⁸ are permitted.
The only valid string renderings of the identifier value are String of decimal digits (0-9), commencing with a non zero digit.
The second and third digits from the right hand end of the string rendering of the identifier must match one of the partition-identifier values specified in this guide.
The rightmost digit of the string rendering is a check-digit and must match the value calculated using the specified check-digit computation.

SCTID Constraints

The permissible value for the SCTIDs are limited by the following rules:

Only positive integer values that are greater than 10⁵ and less than 10¹⁸ are permitted.
The only valid string renderings of the identifier value are String of decimal digits (0-9), commencing with a non zero digit.
The second and third digits from the right hand end of the string rendering of the identifier must match one of the partition-identifier values specified in this guide.
The rightmost digit of the string rendering is a check-digit and must match the value calculated using the specified check-digit computation.

Note

As a result of these rules, many 64-bit integers are not valid SCTIDs. The value limitations enable any valid SCTID to be stored in either a signed or unsigned 64-bit integer.
The rules also ensure that an SCTID can be distinguished from code from one of the antecedent code systems Read Codes(which are 4 or 5 characters in length) and legacy Identifiers from SNOMED RT and it predecessors (which always start with a letter).
SNOMED RT identifiers are SCTIDs identical to those used in SNOMED CT but in some cases will now refer to inactive concepts. In these cases, data in the and can be used to find the identifier of the closest equivalent active concept.

Warning

In some systems and frameworks the default numeric data type is a floating point representation according to IEEE 754. For example, as of today in JavaScript the number type (by default) is a double precision floating precision data type allowing representation of 53-bit integers, which is not sufficient for SCTIDs.

It is recommended that you specify a 64-bit integer type for representing SCTIDs rather than using a default numeric data type. Where a 64-bit integer data type is not available, please use a string data type to represent the SCTIDs.