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The NCI Thesaurus is one of the vocabulary sources included in the NCI Metathesaurus, a vocabulary resource that maps terms from multiple sources to unique concepts identified by a Concept Unique Identifier, or CUI. The NCI Metathesaurus is partially based on the UMLS Metathesaurus; CUIs in the NCI Metathesaurus originate predominantly from assignments made in the UMLS. When NCI Thesaurus concepts are mapped (or merged) to UMLS concepts in the NCI Metathesaurus, they become associated with the CUI of the parent UMLS concepts. If an NCI Thesaurus concept doesn't have an equivalent UMLS concept to merge to, a CUI is still assigned to it; however, this CUI is specific to the NCI
Metathesaurus. In the NCI Metathesaurus, the CUI identifies each concept; in the standalone NCI Thesaurus, the concept code is the actual identifier.

Q.

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Yes, this option is provided in the Curation Tool. You may either search EVS or enter your own valid values. The difference will be that the local valid values will not have a concept class associated with them.

Q. What is the difference between the NCI Thesaurus and the Metathesaurus?

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