LOINC® is a code system for identifying laboratory tests and other observations. It specifies universal codes, names and other attributes for laboratory results as well as clinical reports, physical exam findings, survey instruments and other observations. It was developed to enable the exchange and pooling of results from diverse sources in order to enhance clinical care, outcomes management and research. LOINC is owned, maintained and licensed by the Regenstrief Institute Incorporated (RII).
The Cooperation Agreement between the IHTSDO and RII dated July 2013 states the cooperative work that is to be performed, including the creation of maps, expression associations and content alignments between SNOMED CT and LOINC.
Each LOINC Term that falls within the scope of the Cooperative Work will be associated with a SNOMED CT Expression using the SNOMED CT Concept Model. Each Expression Association links the meaning of a LOINC Term to SNOMED CT, without requiring the creation of a new SNOMED CT Concept. Expression associations will be defined using SNOMED CT Compositional Grammar. Each Expression Association will include an indication of whether it represents a 'sufficient and necessary' (i.e. equivalent to) definition of the LOINC Term, or a 'necessary but not sufficient' (i.e. subtype of) definition of the LOINC Term.