> For the complete documentation index, see [llms.txt](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.b2ihealthcare.com/snow-owl-authoring-platform/7.19.0/reference-sets/reference-set-types/map-type-reference-sets/simple-map-type-reference-sets.md).

# Simple Map type Reference Sets

The Simple Map type Reference Set should be used for one-to-one mappings between SNOMED CT and alternative coding schemes. Although one-to-many mappings are allowed as well. It is possible to map to an external code system, using any of the imported terminologies or code systems as map sources.

To create a new Simple Map type Reference Set, right-click on the Simple Map type Reference Set grouping concept in the **Reference Set View** and select **New Simple Map type Reference Set** and specify:

| Field                         | Description                                      |
| ----------------------------- | ------------------------------------------------ |
| **Preferred term**            | A description for the new Map type Reference Set |
| **Referenced component type** | A SNOMED CT Concept or SNOMED CT Description     |
| **Map target type**           | The Code System of the target                    |

**To add** **members**:

* Click the ![](https://904483993-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M27xKCZNqrmSXSxX0Z1%2Fsync%2F97eef8aca55cb4d4cb15c90811bb45dda317ce45.png?generation=1614789640197346\&alt=media) **Add member button** in the **Reference Set Editor**
* **Drag and drop** concepts from the **SNOMED CT Navigator**
* Use the **SNOMED CT navigator** Context Menu options
  * ![](https://904483993-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M27xKCZNqrmSXSxX0Z1%2Fsync%2F97eef8aca55cb4d4cb15c90811bb45dda317ce45.png?generation=1614789640197346\&alt=media) **Add concept to the active Reference Set** or
  * ![](https://904483993-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M27xKCZNqrmSXSxX0Z1%2Fsync%2F97eef8aca55cb4d4cb15c90811bb45dda317ce45.png?generation=1614789640197346\&alt=media) **Add concept and descendants to the active Reference Set** or
  * ![](https://904483993-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-M27xKCZNqrmSXSxX0Z1%2Fsync%2F97eef8aca55cb4d4cb15c90811bb45dda317ce45.png?generation=1614789640197346\&alt=media) **Add concept descendants only to the active Reference Set** 
* Use the **Search View** Context Menu options
  * **Add concept to the active Reference Set**
  * **Add all results to active Reference Set**

{% hint style="info" %}
These options are only enabled when a **Reference Set Editor** is open and activated.
{% endhint %}

In case of Map type Reference Sets, the **New Member Wizard** pops up requiring to specify a map target or and other properties.\
**Mandatory properties** to be specified in the **New Simple Map Member Wizard**:

| Property                 | Description                                                                                         |
| ------------------------ | --------------------------------------------------------------------------------------------------- |
| **Referenced component** | Refers to the SNOMED CT component that is mapped to the other terminology or Code System            |
| **Map target**           | The target code in the target terminology, classification, or Code System                           |
| **Module**               | Identifies the SNOMED CT module that contains this Reference Set member (primary module by default) |

{% hint style="info" %}
When adding multiple members at the same type, all will receive the same map target value specified in the **Add New Member Wizard**.
{% endhint %}

### Simple Map type with Description Reference Set <a href="#maptypereferencesets-simplemaptypewithdescription" id="maptypereferencesets-simplemaptypewithdescription"></a>

This Reference Set type is a Simple Map type Reference Set, where the Map target description is also displayed.

To create a new Simple Map type Reference Set, right-click on the Simple Map type Reference Set grouping concept in the R**eference Set View** and select **New Simple Map with map target description...**

Members can be added the same way as to a Simple type Reference Set.