A rapid and effective way of deploying SNOMED CT in a national or local implementation is to use SNOMED CT terminology servers. SNOMED CT terminology servers simplify the development of clinical applications that use SNOMED CT, by providing optimized terminology services through an APIs (Application Programming Interfaces). Terminology services may include:

• Searching for SNOMED CT content using term matching, the hierarchy, or defining relationships (see Snowstorm Search Guide),
• Retrieving information about a given concept, including descriptions for a given dialect, supertypes, subtypes and defining relationships,
• Executing Expression Constraint Queries (ECL) on a particular SNOMED CT edition, and
• Accessing maps to/from SNOMED CT and other reference set information.

Terminology servers can either import data from a SNOMED CT release package, or periodically synchronise its content with another terminology server. The loaded SNOMED CT content can then be made available to browsers or electronic health records using a convenient API that implements terminology best practices. Using a terminology server in your implementation can save time, by removing the need to implement these services from scratch. The use of standardized APISs can also simplify their integration into end user applications.

To learn more about using terminology services, please enrol in our SNOMED CT Terminology Services Course (free for Members).

Snowstorm

SNOMED International develops and maintains Snowstorm, a SNOMED CT terminology server built on top of Elasticsearch, with a focus on performance and enterprise scalability. Snowstorm provides the terminology server API for a range of SNOMED CT tools used by SNOMED International, including the SNOMED CT Browser and the SNOMED CT Authoring Platform.

As an open-source tool, Snowstorm can be installed locally to provide a terminology services API to clinical applications.

• Source code: https://github.com/IHTSDO/snowstorm
• Snowstorm Test Instance - Native API: https://snowstorm.snomedtools.org/snowstorm/snomed-ct
• Snowstorm Test Instance - FHIR API: https://snowstorm.snomedtools.org/fhir/
  • NB the Test Instance must not be used in production clinical systems! It has rate limiting and no SLA.

The main features of Snowstorm include:

• Open source, based on a modern open-source stack, Elasticsearch, Spring Boot, Docker
• Advanced SNOMED specific API
• Read-only HL7 FHIR API
• Multi-lingual search and content retrieval
• ECL v2.0 compliant
• Full history (depends on full RF2 import)
• Supports a Read-only mode and an Authoring mode

To deploy Snowstorm in a clinical system, please visit the Snowstorm Github repository to learn how to install your own local instance.

Other Terminology Servers

Other SNOMED CT terminology servers are available, as listed below. Please note that these terminology servers may use different licensing models and APIs (e.g. a standard HL7 FHIR API, or a proprietary API).

This list of terminology servers is provided in alphabetical order. To request the addition or removal of a terminology servers to/from this list, please submit a request via the 'Feedback' button at the bottom of this page.