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Unified Medical Language System® (UMLS®)

Logical Observation Identifiers Names and Codes (LOINC®)

04/06/09 Owners of LOINC, NPU, and SNOMED CT Begin Trial of Cooperative Terminology Development

LOINC® (Logical Observations Identifiers, Names, Codes), is a clinical terminology important for laboratory test orders and results, produced by the Regenstrief Institute.

LOINC is one of a suite of designated standards for use in U.S. Federal Government systems for the electronic exchange of clinical health information. LOINC is likely to become a HIPAA standard for some segments of the Claims Attachment transaction. In 1999, it was identified by the HL7 Standards Development Organization as a preferred code set for laboratory test names in transactions between health care facilities, laboratories, laboratory testing devices, and public health authorities.

NLM supports the ongoing development of LOINC through a contract arrangement.

Additional information about LOINC and its representation in the UMLS Metathesaurus is available:

     LOINC, a universal standard for identifying laboratory observations

Last Reviewed: February 17, 2015