• Version: Snow Owl v2.5
  • Start date: 11 March 2013
  • End date: 19 April 2013
  • Code name / adopted animal: Basil, an Asian lion at the Budapest Zoo


LOINC (Logical Observation Identifiers Names and Codes) is used to identify medical laboratory observations. The latest version of LOINC is now available in Snow Owl. A view and an editor have been added to display LOINC content, it’s also possible to search for LOINC content.


Icons are used to distinguish different LOINC parts (e.g. fertility testing, skin tests).

LOINC View, top-level grouping

Browsing LOINC

The LOINC view displays the short-names of the codes as a tree structure. Clicking on the triangles allows you to browse the multi-axial hierarchy. The functions in the navigator are similar to the other views (e.g. SNOMED CT).

LOINC View, top-level grouping

Search LOINC

Searching for LOINC codes works similar to searching within other terminologies.

Quick search allows a comprehensive search across all terminologies and classification systems. Search results for LOINC appear as a new category (see screenshot).

Quick search results displaying matches from SNOMED CT, ICD-10, and LOINC

The filter search in the LOINC view allows to display only matching terms in the hierarchy.

LOINC filter search results

A LOINC tab was added to the Advanced search dialog. Searches can be made based on Code and Label.

LOINC advanced search dialog

The Results are displayed in the Search View.

LOINC search results

LOINC editor

The LOINC editor displays information about a selected LOINC code. Double-click on a code in the LOINC view to open the editor. The editor is grouped in three pages:

  • Overview: Displays concept names, basic properties, status, changes, and ranking.
  • Observation Information: Displays information related to observation, e.g. substance, units, survey information.
  • HL7: Displays HL7 related properties

Click on the tab at the bottom of the editor to view a page.

LOINC Editor – Overview page

Note: The editor is read-only.

Mapping between SNOMED CT and LOINC

The simple map type reference set can be for one-to-one mappings between SNOMED CT and LOINC.


To map between SNOMED CT and LOINC, you have to create a simple type reference set.

  • Use the button in the toolbar to create a simple type reference set.
  • Choose SNOMED CT concept as the Referenced component, and LOINC concept as Map target type. Save the reference set.

Creating a simple type reference set for mapping SNOMED CT to LOINC

Now you can add members to the reference set.

  • To launch the wizard, simply click the Add member button in the toolbar of the reference set editor. It’s also possible to drag a SNOMED CT concept from the view to the reference set editor to open the wizard.
  • Use the browse button to bring up the quick search where you can select a referenced component from SNOMED CT.
  • Now use the browse button to bring up the quick search with LOINC codes to select a map target from LOINC.
  • Click Finish to confirm the mapping, and Save the changes.



When mapping from LOINC to SNOMED CT the components, you should use the following settings: Referenced component: LOINC concept Map target type: SNOMED CT concept.

Apart from that the process of mapping is similar to the one described in the section above.

Export delta by effective dates

You can now export delta by any combination of effective dates.

  • Go to File < Export < Snow Owl < SNOMED CT to RF1 and RF2 to open the export wizard.
  • Select Delta export, and specify starting and finishing effective date.
  • Check the components you want to export. Review components and hit Finish to start the export.

Exporting Delta version

ATC editing

Create new ATC code

To create a new ATC code, go to the ATC navigator, right click the parent, and select Add new child concept.

Creating a new ATC code

This will open the new code in the editor.

  • Concept label: By default, the label of the parent is used for the new code. To change the label, simply type in the text field.
  • Concept ID: A new ATC code ID is automatically generated, which can be saved. If you want to change the code ID, make sure that they are consistent with the coding system. Once you are done editing, save your changes.

Entering an ATC code name

The new ATC code is now visible in the ATC navigator and can also be found in searches.

Note: To avoid confusion, please keep in mind that the ATC Classification system consists of codes and not of concepts such as SNOMED CT. An ATC code is comprised of a code ID and a code label.

Code validation

The code validation prevents you from authoring invalid codes, because errors have to be fixed before saving. An error message in the editor will inform you about the kind of problem. For example, if you make a change to the code ID that is not consistent with the coding format or if the change points to a a different parent than it was created for. Click on the link to go to the respective text field.

ATC code validation

Edit ATC label

The ATC label gives information about the content of a code.

It’s also possible to make changes to an existing ATC code.

  • Open the code in the editor,
  • Enter your changes in the Concept label text field, and
  • Save the changes.

The new ATC label will appear in the ATC navigator.

Delete ATC code

You can delete an ATC code by right-clicking the code in the ATC navigator and selecting Delete concept. You will be presented with a deletion plan, click Finish to proceed.

Note: ATC editing feature is only available in standalone mode.


This release includes several features related to description logic classification. Note that as these features require additional memory, they are only available when using Snow Owl in collaborative mode with a terminology server.

  • Automatic reasoner selection: Like an automatic transmission in your car, the selection of the reasoner is now automatically based on your ontology.
  • Incremental classification: Incremental classification saves time by only processing axioms that have been changed.
  • Server-side classification: This allows the classification to be performed on the server instead of the client when running in collaborative mode. This allows multiple processors and more memory to be used to reduce the classification time.

Classification services now run on the server