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Unified Medical Language System® (UMLS®)

MRSAB.RRF Fields and Descriptions


FieldFull NameDescription
VCUI Versioned CUI CUI of the versioned SRC concept for a source, which contains the full and abbreviated names used for this version of this source
RCUI Root CUI CUI of the root SRC concept for a source, which contains the full and abbreviated names used for this version of this source
VSAB Versioned Source Abbreviation The versioned source abbreviation for the source, e.g., MSH2009_2008_08_06
RSAB Root Source Abbreviation The root source abbreviation for the source, e.g., MSH
SON Source Official Name The full official name for the source, e.g., Medical Subject Headings
SF Source Family The RSAB value of the primary source in this source's family. Some sources are part of related "families"; e.g., the MTHHH source consists of hierarchical terms intended for use with the HCPCS source, so the source family for MTHHH (as well as for HCPCS itself) is set to "HCPCS"
SVER Source Version The source version, e.g., 2009
VSTART Meta Start Date The date a source became active, e.g., 2001_04_03; for MEDLINE co-occurrences (RSAB=MED) this specifies the date when the co-occurrence data was sampled)
VEND Meta End Date The date a source ceased to be active, e.g., 2001_05_10
IMETA Meta Insert Version The version of the Metathesaurus in which a source first appeared, e.g., 2001AB
RMETA Meta Remove Version The version of the Metathesaurus in which the source last appeared, e.g., 2001AC
SLC Source License Contact Source contact for inquiries about licensing this source
SCC Source Content Contact Source contact for inquiries about the content of this source
SRL Source Restriction Level values are 0, 1, 2, 3, 4, 9; categories are explained in the UMLS License Agreement; for details: see UMLS License Agreement)
TFR Term Frequency The number of names provided by this source, i.e., the number of distinct strings (SUIs) it has in MRCONSO.RRF
CFR CUI Frequency The number of concepts (CUIs) containing one or more names from this source
CXTY Context Type
  • The type of contexts for this source. Values are: FULL, FULL-MULTIPLE, FULL-NOSIB, FULL-NOSIB-MULTIPLE,FULL-NOSIB-MULTIPLE-IGNORERELA, Null.
  • All sources with contexts now have "full" contexts, i.e., all levels of terms may have Ancestors, Parents, Children and Siblings. (Early versions of the Metathesuarus included only partial contexts for some sources.) A full context may also be further designated as Multiple, Nosib (No siblings) or both Multiple and Nosib, as well as "Ignore-RELA".
  • "Multiple" indicates that a single concept in this source may have multiple hierarchical positions.
  • "Nosib" (no siblings) indicates that siblings are not represented in the contexts for this source.
  • "IgnoreRELA" indicates that the source's hierarchical RELA (relationship attribute) values were not used when computing ancestors/descendants.
TTYL Term Type List The list of Term type values used to categorize the types of atoms in the source, e.g., MH, EN, PM, TQ
ATNL Attribute Name List Attribute names (from MRSAT.RRF) used for the source, e.g., MUI, RN, TH
LAT Language The 3 letter code for the language of the terms in the source
CENC Character Encoding All UMLS content is now provided in Unicode, encoded in UTF-8. The MetamorphoSys software will allow exclusion of extended characters with some loss of information. Transliteration to other character encodings is possible but not supported by NLM; for further information, see
CURVER Current Version Y or N flag indicates whether or not this row corresponds to the current version of the named source
SABIN Source in Subset Y or N flag indicates whether or not this row is included in the current MetamorphoSys subset. (Always Y where CURVER is Y, but if the MetamorphoSys software is used to remove this source from a customized subset, it will be changed to N)
SSN Source Short Name The short name of the source assigned by NLM and as used by the NLM Knowledge Source Server; in general, this is longer than the SAB (source abbreviation) but may be shorter than the SON (source official name)
SCIT Source Citation Bibliographic citation information for the source.


For more information, see Section 3.3.15 Source Information (File = MRSAB.RRF) in the UMLS Reference Manual.

Last Reviewed: July 29, 2016