Common Terminology Services 2™ (CTS2™)

Structured Terminology for Medical Vocabulary

Common Terminology Services 2™ (CTS2™)

Common Terminology Services 2™ (CTS2™) is a functional standard defining the capabilities, responsibilities, inputs, outputs, and expected behavior defining a set of core functionality to support the management, maintenance, and interaction with ontologies and medical vocabulary systems. 

Structured terminologies provide a foundation for information interoperability by improving the effectiveness of information exchange. They provide a means for organizing information and serve to define the semantics of information using consistent and computable mechanisms. Terminologies are constructed to meet scope specific domain requirements. The domain-specific nature of structured vocabularies often leads to variation in design patterns across the available terminology space.

The ability to provide consistent representation and access to a broad set of terminologies enables multiple disparate terminology sources to be available to a community, and helps to ensure consistency across the domain space of that community. Service interfaces to structured terminologies should be flexible enough to accurately represent a wide variety of vocabularies and other lexically-based resources.

The PIM specified in this document for CTS2 is intended to mediate among disparate terminology sources by providing a standard service information and computational model. The Information Model specifies the structural definition, attributes and associations of Resources common to structured terminologies such as Code Systems, Binding Domains and Value Sets. The Computational Model specifies the service descriptions and interfaces needed to access and maintain structured terminologies

This specification defines a platform-independent model (PIM) that specifies an Information Model as well as a Computational Model. Conformant

implementations of this PIM must provide an implementation that represents both the Information Model and Computational Model. This base level implementation provides the foundation for providing data type specific profiles (i.e., ISO 21090 data types, HL7 data types, etc.)

With formal support from 14 separate organizations, CTS 2 encompasses the best practices and ideas of the terminology management and user community.


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