# Release File Data Types

The following data types are used in the release files:

**Data Types Used in Release Files**

<table data-header-hidden data-full-width="true"><thead><tr><th width="117.2421875"></th><th width="800"></th></tr></thead><tbody><tr><td><strong>Data Type</strong></td><td><strong>Description</strong></td></tr><tr><td>SCTID</td><td><p>A SNOMED CT identifier, between 6 and 18 digits long, as described in <a href="../../snomed-ct-identifiers/6.2-sctid-representation">SCTID Representation</a>.<br></p><ul><li>This data type is used to identify SNOMED components, to refer to a component from another component or from a reference set, and also to represent the values for concept enumerations.</li></ul></td></tr><tr><td>UUID</td><td><p>A Universally Unique Identifier is a 128-bit unsigned generated using a standard algorithm.</p><ul><li>UUIDs are represented as strings of hexadecimal characters split by - characters as points specified by the <a href="https://en.wikipedia.org/wiki/Universally_unique_identifier">UUID standard</a>.</li></ul></td></tr><tr><td>Integer</td><td>A 32-bit signed integer.</td></tr><tr><td>String</td><td>UTF-8 text of a specified length.</td></tr><tr><td>Boolean</td><td>A Boolean value, represented as one of two possible integer values (1 = true, 0 = false).</td></tr><tr><td>Time</td><td><p>A date and time format expressed as a text string in line the basic representation specified in the <a href="https://en.wikipedia.org/wiki/ISO_8601">ISO 8601 standard</a>.</p><ul><li>Where only date is required the format is YYYYMMDD (e.g. 20180125 refers to 25th January 2018)</li><li>Where a time is also required the <em>YYYYMMDDThhmmss</em>Z (e.g. 20180125T123000Z refers to 12:30 UTC on 25th January 2018)</li><li>The time should be expressed as UTC, as indicated by the trailing "Z".</li></ul></td></tr></tbody></table>

***

## Concept Enumerations

Concept enumeration is the a set of SNOMED CT concept identifiers used to represent values for a property of a SNOMED CT component or reference set member.

**Notes**

* *Concept enumeration* serves the same purpose as more general approaches to providing enumerated lists of values (i.e. assigning a number to a value). However, the use of SNOMED CT concept identifier allows access to the human readable meaning of each enumeration using descriptions in the same way for other concepts.
* The SNOMED CT concepts used to represent *concept enumerations* are usually subtype children (or descendants) of concepts in the SNOMED CT metadata hierarchy. Each possible value is represented by a single child concept. This allows updates to the permitted values to be tracked using the component history mechanism.

**Example**

Concept enumerations for description.typeId:

* 900000000000446008 <mark style="color:blue;">|</mark>Description type (core metadata concept)<mark style="color:blue;">|</mark>
  * 900000000000003001 <mark style="color:blue;">|</mark>Fully specified name (core metadata concept)<mark style="color:blue;">|</mark>
  * 900000000000013009 <mark style="color:blue;">|</mark>Synonym (core metadata concept)<mark style="color:blue;">|</mark>
  * 900000000000550004 <mark style="color:blue;">|</mark>Definition (core metadata concept)<mark style="color:blue;">|</mark>

***

**Concept enumeration values (subtypes of 900000000000442005&#x20;**<mark style="color:blue;">**|**</mark>**Core metadata concept**<mark style="color:blue;">**|**</mark>

<table data-header-hidden data-full-width="true"><thead><tr><th></th><th></th></tr></thead><tbody><tr><td><strong>Concept</strong></td><td><strong>Comment</strong></td></tr><tr><td><p>900000000000443000</p><p><mark style="color:blue;">|</mark>Module (core metadata concept)<mark style="color:blue;">|</mark></p></td><td>Each subtype of this concept represents a development module. These concepts provide values to the moduleId field that is present in all SNOMED CT component file. The value indicates the module within which a component was created and is being maintained.</td></tr><tr><td><p>900000000000444006</p><p><mark style="color:blue;">|</mark>Definition status (core metadata concept)<mark style="color:blue;">|</mark></p></td><td>Each subtype of this concept represents a value that can be applied to the concept. definitionStatusId field. This is used to indicate whether the current set of defining Relationships applied to a concept are sufficient to fully-define it relative to its supertypes.</td></tr><tr><td>900000000000446008 <mark style="color:blue;">|</mark>Description type (core metadata concept)<mark style="color:blue;">|</mark></td><td>Each subtype of this concept represents a value that can be applied to the Description. typeId field. This is used to indicate whether the Description represents a Fully Specified Name, a synonymous term, a definition or some other symbolic or textual representation of the associated concept.</td></tr><tr><td><p>900000000000449001</p><p><mark style="color:blue;">|</mark>Characteristic type (core metadata concept)<mark style="color:blue;">|</mark></p></td><td>Each subtype of this concept represents a value that can be applied to the Description. caseSignificanceId field. This is used to indicate whether the text of the term can be modified to by switching characters from upper to lower case (or vice-versa).</td></tr><tr><td>900000000000449001 <mark style="color:blue;">|</mark>Characteristic type (core metadata concept)<mark style="color:blue;">|</mark></td><td>Each subtype of this concept represents a value that can be applied to the Relationship. characteristicTypeId field. This is used to indicate whether a Relationship forms part of the definition of the source concept.</td></tr><tr><td><p>900000000000450001</p><p><mark style="color:blue;">|</mark>Modifier (core metadata concept)<mark style="color:blue;">|</mark></p></td><td>Each subtype of this concept represents a value that can be applied to the Relationship. modifierId field. This is used to indicate the type of Description Logic (DL) restriction (some, all, etc.) that applies to the Relationship.</td></tr><tr><td>900000000000453004 <mark style="color:blue;">|</mark>Identifier scheme (core metadata concept)<mark style="color:blue;">|</mark></td><td>Each subtype of this concept represents a value that can be applied to the Identifier. identifierSchemeId field. This is used to indicate the scheme to which the Identifier value belongs.</td></tr></tbody></table>

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