C0450066

UMLS CUI C0450066 is "Railway employee on train".

Railway employee on train (CUI C0450066) groups: 1 SNOMED CT concept.

Railway employee on train corresponds to SNOMED CT concept 257521003.

The Unified Medical Language System is the NLM's meta-terminology that unifies SNOMED CT, ICD-10, ICD-11, RxNorm, LOINC, MeSH, and around 200 other source vocabularies under a single concept identifier (CUI). One UMLS CUI can group dozens of synonymous codes from different terminologies.

A CUI is a stable identifier (like C0011860) that points at a single clinical idea regardless of how that idea is encoded in any specific vocabulary. CUIs are the most reliable way to bridge between terminologies when you need to compare or merge data from multiple sources.

Every UMLS concept page lists the codes it groups together. That gives you a free crosswalk: a SNOMED concept and an ICD-10 code that share a CUI describe the same clinical idea. Our cross_references API returns these groupings inline.

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