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The Value Set Authority Center (VSAC) is a value set authoring tool and repository. It is the source of truth for value sets for CMS's electronic clinical quality measures. The National Library of Medicine maintains the VSAC and provides access via web browsers and APIs. The VSAC provides downloadable resources for all measure releases that provide full eCQM value sets, the Binding Parameter Specification, and the complete lists of Direct Reference Codes, retired codes, and utilized code systems. The VSAC provides users with tools to search existing value sets, create new value sets, and maintain value set content consistent with current versions of the terminologies they use. Access requires a free Unified Medical Language System License

Who Uses Tool
CDS Developer/Steward
Eligible Hospital / Critical Access Hospital
Eligible Clinician
Health IT Developer/Vendor
Measure Developer/Steward
Last Updated: Apr 08, 2024