The Snow Owl 5.1 release was focusing on reference set related operations. Besides the new features, a number of old functionalities from the 4.6 version have been migrated to work under the 5.x.

New features

Reference set combinations

A new dialog allows creating all sorts of logical combinations from two simple type reference sets, including merging them as a union or an intersection, or splitting the intersection from one.

The following methods are available to combine two simple type reference sets named A and B:

  • Union – A U B: the resultant set contains all the elements in either A or B or both
  • Intersection – A Ո B : the resultant set contains the elements present in both A and B
  • Complement A-B – A\B : the resultant set contains everything in A but not present in B
  • Complement B-A – B\A : the resultant set contains everything in B but not present in A
  • Symmetric difference – (A\B) U (B\A) : the resultant set is the intersection substracted from the union


Reference set combinations

Combine Reference set wizard

You can preview the results and the number of concepts found in the dialog.


Review resulting concepts

The resulting concept sets can be saved as a new reference set.

Specifying the Preferred term of the new reference set

Specifying the Preferred term of the new reference set

Map block type reference set

SNOMED CT to OPCS-4 map block type reference sets are supported for importing and authoring. The full functionality of the reference set will be completed with the OPCS-4 support.

Flag decorator

United Kingdom Edition concepts are marked up with a tiny UK flag decorator in the concept and reference set navigators and in the reference set editor..

United Kingdom flag indicating the concept provenance

United Kingdom flag indicating the concept provenance

Migrated functionalities

Value set support

Non-SNOMED CT specific concept set creation is added back. A dedicated perspective supports the import/creation and update of value sets.

The value set view (also called value set navigator) works similar to other views:

  • Value sets are organised by category. Categories can be expanded Expandall.png and collapsed Collapseall.png.
  • You can link the value set editor to the value set view with the Link-editor.gif button.
  • A filter allows to search for value sets.


Refset advanced search

Besides the quick search and the navigator filter, the advanced search now supports searching for reference sets by type, referenced component type or module.

Drag and drop

Members can be dragged and dropped into simple type reference sets to support quick editing and eliminate the use of wizards.


The informative tooltips have been added to the concept editor overview page to display more details on relationships and descriptions.

Batch member editing

Search and semantic query results and subhierarchies can be added to a simple type reference set with a single click using the context menu. This allows more effective batch member editing.

Link editor with navigator

You can connect or disconnect the SNOMED CT editor to the SNOMED CT view. If the link button Link-editor.gif is activated a concept that is selected in the editor, is also displayed in the tree of the SNOMED CT view allowing you to see where it’s located in the hierarchy.