iaward 2011

An Eclipse-based application designed to support describing the meaning of terms in existing clinical terminologies.

Snapper Platform

Download Snapper
Last Updated 2 June 2014 for Snomed CT AU-20140531 and AMT v2.56 (May 2014) – (also includes an experimental combined Snomed CT-AU and AMT of previous versions)

Snapper is a Licenced product and can only be downloaded after obtaining a Licence. Please email for further information on obtaining a Snapper Licence.

The Snapper Platform is an Eclipse-based application designed to support describing the meaning of terms in existing clinical terminologies using concepts or expressions from SNOMED CT. However Snapper is not bound to SNOMED CT, and other ontologies can be used as an alternate target ontology.

Semantic Mappings to SNOMED CTâ„¢

The SNOMED CT ontology has been identified world-wide as the standard clinical terminology to be used when collecting clinical information about a patients treatment yet whilst vast, its coverage can be patchy, particularly in specialist areas. To ease the adoption of SNOMED CT for clinical data collection, it may be desirable to create a semantic mapping from an existing set of terms to SNOMED CT. In opther words, to specify specifically the relationship between a term and a single SNOMED CT concept, or an expression composed of multiple concepts.

Snapper allows a list of ad-hoc terminology source terms from an existing data set to be imported and mapped to SNOMED CT using SNOMED’s post-coordination expression syntax. Realising from the outset that post-coordination of concepts is difficult, an expression editor was designed with features similar to a smart program editor, such as colour-coded syntax highlighting, automatic description completion and a templating engine driven by the SNOMED CT concept model.


  • The Automap feature attempts to automatically generate the simplest of mapping expressions – a one to one mapping which can cut down the mapping workload considerably. Additionally, users can write a script to perform some of their own mapping, allowing for handling of common abbreviations or other features specific to the source terminology.
  • Drag and drop of concepts into the expression editor from the search results view and the graphical visualization was added as a first step to supporting a direct manipulation approach to composing expressions.
  • Many people interact with SNOMED CT terms and not the underlying concept identifiers. Concept identifiers feature heavily in our expression editor, and whilst this conforms to the official SNOMED CT documentation, alternative visual representations supporting user interfaces metaphors such as direct manipulation will better cater for this group of users.
  • Many users have no experience with the SNOMED CT compositional grammar and the syntax is somewhat obscure and unintuitive. Ideally the editor should handle these details of the grammar and support the user’s goals of identifying the focus concept for mapping and then mediate its subsequent refinement based on the Concept Model constraints.
  • There are general mapping patterns, akin to software design patterns, that represent a set of best practices in mapping, developed over time. To assist in the authoring of mappings with reproducible quality and ease repetitive mapping tasks, the tool should support user-specified workflows and templates to capture these patterns.

License Requirements

Before downloading this product you must obtain the following Licences ..

  • SNOMED CT® Affiliate Licence
  • Australian National Terminology Release Licence (For Australians, both of these are available from nehta)
  • Snapper Licence (Please email for further information on obtaining a Snapper Licence.)

System Requirements

Java 1.6 (1.7 will not work)

(Many computers will already have this installed. It is a free download that your IT support group should be able to help you install if you don’t already have it.)

Installation Instructions

Pre-packaged Snapper Installation Instructions

How to Use Snapper

Help for Snapper is available within the application. To launch the help from within Snapper, choose “Help Contents” from the “Help” menu and expand and browse through the “Snapper” topic. It is also possible to search the help and print it out if you prefer a hardcopy reference.

Feedback or problems with Snapper?

If you would like to provide any feedback on Snapper or report a bug, please email

If your enquiry relates to licencing, please email

Snapper FAQ

Q. I am getting an error message that says “The folder C:minnow-workspace.metadata” is read-only. What’s going on?

A. The default location for the workspace is in your user directory. It sounds like someone has changed the location of the workspace in order to share it between multiple users on the one computer. You need to also make sure that this new location is one that all users have (write) access to.