New features


ICD-10 Import

ICD-10 Import

Snow Owl now supports importing ICD-10 releases in ClaML format. Please note that due to licensing restrictions, Snow Owl does not distribute the ICD-10 release which will need to be obtained from the World Health Organization. The import process is fairly quick, taking less than a minute for the full 2010 release.

ICD-10 Navigator

ICD-10 Navigator

The ICD-10 Classes navigator allows viewing the hierarchical relationships of the ICD-10 codes. Users can expand the chapters down to the four-character subcategories. Each node display both the ICD-10 code and label.

ICD-10 navigator showing filter search on 'infarct'

The ICD-10 navigator functions like other terminology navigators in Snow Owl, supporting filter search, displaying filter results hierarchically, linking with the open editor, setting a concept as the root node and returning to the default root node, etc.

ICD-10 Editor

ICD-10 Editor

Double-clicking any of the nodes opens the code in a read-only editor. The editor has two tabs, one for reviewing the details and the other for displaying any mappings that reference the code. The Overview tab displays the code, the label and the descriptions and the inclusion and exclusion codes with hyperlinks. The Mappings tab displays the mappings in which this code is participating.


Support has been added to import, display, and edit SNOMED CT to ICD-10 mappings. In IHTSDO parlance, these are SNOMED CT RF2 Complex Map Type Reference Sets, often referred to as "complex maps."

Import SNOMED CT complex maps

Snow Owl includes the SNOMED CT to ICD-10 Cross Map Preview release under development by IHTSDO and the World Health Organization. Note that this cross map is still under development by the IHTSDO SNOMED CT to ICD-10 Mapping Workbench project group and they welcome your feedback.

Complex map type reference sets

Since Snow Owl does not ship with ICD-10, an additional step is required to fully integrate the cross map with SNOMED CT and ICD-10. Once the ICD-10 release has been imported, the mapping can be updated with details from the ICD-10 release. This makes navigation easier, as instead of an identifier, the actual ICD-10 code and label is displayed with an associated icon to identify the top-level parentage.

Invoke update map target action from context menu

Update map target with selected terminology component

Create and edit SNOMED CT to ICD-10 Complex maps

It is now possible to create a new complex map, or add additional members to the ICD-10 Complex map type reference set that has already been imported.

Complex map type reference set editor with ICD-10

For creating a complex map you need to select the icon from the main toolbar, or get to the New Reference Set Wizard and select Complex Map Type reference set.

For adding a new reference set member, besides the basic properties, the user can select from a variety of pre-defined map rules and map templates and populate them with the appropriate SNOMED CT and ICD-10 identifiers that apply to the member.

Export SNOMED CT Complex map

We now support exporting complex maps in SNOMED CT RF2 format.

Exporting complex map reference sets

Refset enhancements

Refset comparison

A reference set comparison feature has been added to identify inclusion relationships between reference sets. This allow determining:

The compare wizard can be opened from the reference set view.

Invoke Compare action from context menu

Results of refset comparison

The comparison engine utilizes all available processing cores to speed subsumption calculation.

Linkage set generation

If subsumption is found between the reference sets, the user can generate a linkage set--a simple type reference set containing the transitive closure relationships between the members.

Linkage set

Further constraining a master reference set

The user can now further constrain or extend a reference set by creating a clone of it and adding modifications either manually or by using lexical or semantic queries. The master reference set will remain the same, while various versions can be created with the clone mechanism for modifications. The clone action can be invoked by right-clicking the reference set in the Reference Set navigator.

Invoke Clone reference set action from context menu

Clone reference set wizard

Validate reference sets

Reference sets can now be validated to ensure that all referenced components are active. The validation can be invoked by right-clicking the reference set in the navigator.

Invoke validate reference set action from context

The validation errors are displayed in the Problems view, and error-decorators are also added to the reference sets and reference set members where erroneous components are found.

Validation error markers on reference set in Reference set navigator

The problems view displays additional information about the erroneous members. Note that in this example, the refset member is active (indicating that this component is a current part of the refset), however the referenced component itself (Infection by Babesia equi) is inactive.

Erroneous reference set member in problems view

Erroneous reference set member in editor

Derive reference sets from Simple maps

Three different methods has been implemented to derive simple type reference sets from the SNOMED CT components that participate in simple maps. Each can be initiated by invoking the reference set derivation wizard from the Reference set navigator's context menu.

Reference set derivator wizard

Generate simple type reference set from SNOMED CT components

This feature generates a simple type reference set of the SNOMED CT components that participate in a mapping.

Generate transitive closure refset from mapping

This feature creates a simple type reference set of the SNOMED CT components that participate in a mapping. In addition to the actual referenced components in the mapping, all of the subtypes of these concepts are also included.

Generate trio refset from mapping

This feature creates a trio of ‘concept’, ‘description’, and ‘relationship’ simple type reference sets from the SNOMED CT components of the mapping, where the ‘relationships’ are the minimum set of defined (including is_a) relationships that exist between the given concepts.

Flat file import

Import spreadsheet

Spreadsheets from .xsl or .csv format can be imported into the workspace to support automapping with external codesystems and terminologies.

Create new automap file

Automap file in project explorer

By using the labels of the external codes, map sources can be specified manually or automatically with SNOMED CT lexical search.


Clicking on the icon runs a lexical search for each of the labels from the external terminology, and inserts the appropriate SNOMED CT concept when exact match has been found for an active concept. For those items that do not have a matching map source, manual search helps to select the SNOMED CT concept.

Automapper dialog

Convert to simple map

Clicking on the Generate simple map type reference set icon creates a Simple map type reference set of the completed map associations. The map target can be selected to be either the code or the label of the external terminology. The automap file can be further edited, and a simple map type reference set can be generated any time.

Generate simple map type referennce set from automap file

Validate unique Fully Specified Names

When creating a new concept, the fully specified names are validated immediately to ensure that the Fully Specified Names remain unique in the ontology.

Check for FSN uniqueness in new concept wizard

Displaying relationships

With the addition of the reference set and linkage set generation features, we are more frequently displaying relationships to the user. To make this simpler to interpret, we are now displaying the preferred terms for the source, attribute, and destination concepts for each relationship.

For example, when deleting unpublished components, the deletion plan now displays 'Viral fever Is a Clinical finding' as the relationship label:

Deletion plan displaying relationship