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Common Terminology Services 2 (CTS 2)

SDO Owner
CTS2 Technical Specification
Provides technical interfaces with bindings into SOAP and REST supporting CTS2 functions.
Accepting public comments/corrections through 2013-MAR-08

Note: The CTS2 Community has a resource center as part of the Health Ingenuity Exchange (HingX), where CTS2 assets and community discussions are available. The community is open to all interested individuals. Please visit HingX

Looking for the current CTS2 Technical Submission Wiki? Go **here**

Link to CTS2 Initial Specifications

Initial CTS2 Submissions to the OMG

To contribute comments regarding the CTS2 initial specification, please contact the individuals listed as the points of contact for each submission.

Description of the Proposed Service

The Health Level Seven (HL7) Version 3 standards are based on a Reference Information Model (RIM) which is flexible and general in structure. Representation of information within this model is dependent on the availability of terminological resources which can be used to populate the properties of the model with appropriate semantic content.

CTS 2 will expand on the original functionality developed in HL7s Common Terminology Service specification (CTS), specifically looking to:

  1. Establish a common model for terminology, and how it is related to meta-data (models of data) and data (the information itself)
  2. Integrate into CTS 2 the functional coverage outlined in the existing CTS specification:
    1. Rephrase CTS it in terms of the Service Functional Model (SFM) and abstracting out HL7 dependencies
    2. Removing the existing implementation specification to enable re-specification using standardized tools and mappings that have emerged since the original CTS adoption
  3. Specify both an information and functional model that addresses the relationships and use of terminology in data – how data elements are constrained to ranges of possible codes, how selection lists built and queried, how terminological information is validated.
  4. Specify the interactions between terminology providers and consumers – how users can submit unambiguous requests for corrections and extensions and how revisions to content are identified, distributed and integrated into running systems.
  5. Specify how mapping between compatible terminologies and data models is defined, exchanged and revised.
  6. Specify how logic-based terminologies can be queried about subsumption, classification and inferred relationships.

The Reason Why This Service is Needed

CTS deliberately steered clear of producing a dynamic model of terminology, avoiding issues related to terminology distribution and versioning. The value set, or sub-setting section of CTS focused on static value sets and didn’t fully address the definition or resolution of value sets that define post-coordinated expressions – issues that are now in scope due to the maturing Terminfo/SNOMED Concept Model Working Group (CMWG) model , and Terminfo.

The Reason Why a Standard is Needed for this Service

The CTS specification has begun to be adopted by organizations that recognizing that the existing CTS standard serves an important role in defining the common functional characteristics that an external terminology must be able to provide. However, these organizations are also realizing that CTS fails to address many of the issues that are required for a truly interoperable “semantics of terminology”.

CTS 2 will be a commonly accepted standard for terminology services that enhances the capabilities of the initial CTS specification for sub-setting and mapping, and extends the specification into domains such as terminology distribution, versioning, and classification. Standardizing this functionality at this level will allow applications using terminology services to build on a common infrastructure, and improve interoperability at the terminology layer across applications.

CTS 2 Navigation

HL7 Common Terminology Services - Release 2 DSTU
Initial CTS2 Submissions to the OMG
CTS 2 Sub-Sections and Scope
Functional Characteristic Catagories
Sources of functionality
CTS 2 Approach
Meetings and Minutes
Active Work Products
CTS 2 Reviewer Comments