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LNC (LOINC) - Source Representation


This page lists specific source data elements and provides information on their representation in the UMLS Metathesaurus.

VSAB: LNC274


Summary of Changes:

1. New Class:

Abbreviation Class
PANEL.EYE.SPECULAR MICROSCOPY Specular microscopy panel
PANEL.SURVEY.CoVSocEcon SARS-CoV-2 Related Socioeconomic Questionnaire panel
SURVEY.CoVSocEcon SARS-CoV-2 Related Socioeconomic Questionnaire survey

Source-Provided Files: Summary

The complete LOINC distribution includes the following.

Documentation and Reference:

All data files have accompanying ReadMe and ReleaseNotes text files. In addition, LOINCUsersGuide.pdf provides detailed information.

Data files

File Name Description
Loinc.csv Primary LOINC data files
MapTo.csv Mappings between current and retired codes
ComponentHierarchyBySystem.csv The records in this file represent nodes of the hierarchy, whether LOINC Parts or full LOINC codes.
The ordered sequence at any level of the hierarchy is given by the SEQUENCE field.
Top level nodes in the hierarchy are those where PATH_TO_ROOT is null. This is a "Comma Separated Value" text file.
Parts.csv Parts names and codes
PartLinks.csv Part links, for relationships and hierarchy
PanelsAndForms.csv Mappings between LOINC panels and their members.
LoincAnswerListLink.csv Links LOINC terms with associated Answer Lists
AnswerList.csv Data for Answer Lists that are associated with any of the LOINC terms included in the current LOINC release.
LoincUniversalLabOrdersValueSet.csv Members of the LOINC Universal Lab Orders Value Set
LoincIeeeMedicalDeviceCodeMappingTable.csv Linkages between LOINC terms and content from the IEEE 11073(TM) 10101 Standard for Health informatics - Point-of-care medical device communication - Nomenclature and 10101a Nomenclature Amendment.
LoincRsnaRadiologyPlaybook.csv Linkages between LOINC radiology terms, the attribute values of the Unified Model as both LOINC Parts and RadLex terms, and any applicable mappings to RadLex Playbook terms.
ImagingDocumentCodes.csv A subset of document codes in LOINC that represent imaging procedures and reports.
ConsumerName.csv LOINC term Consumer Names
Group.csv Data representing unique Groups. Includes parent, inactive, and deprecated groups.
GroupLoincTerms.csv Data representing unique Groups and their unique LOINC terms
GroupAttributes.csv Data representing unique Groups and their attributes
ParentGroup.csv Data representing unique Parent Groups
ParentGroupAttributes.csv Data representing unique Parent Groups and their attributes

Not included:
Loinc.csv:Fields that are for internal (LOINC) use are not processed for the Metathesaurus.
Fields that are not used are indicated by "Not used" in the "Representation" columns below.


Source-Provided Files: Details

Details on format of input files and representation of source data. Consult the LOINC documentation for additional details.

file: Loinc.csv

# Field Description Representation
1 LOINC_NUM Unique Code; format is #####-# MRCONSO.CODE, SCUI
2 COMPONENT Fields 2-7 contain the six parts of the name.
The fully-specified name for a given LOINC code is constructed by concatenating the contents of these fields, inserting a colon (":") between each element.
  • First segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LN" or "LO"
  • First segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LX" or "OLX" (with expansions)
  • Subfield 1 = MRCONSO.STR, TTY = "CN"
  • MRCONSO.STR, TTY = "CX" (subfield 1, with expansions)
  • Entire field: MRSAT.ATN = LOINC_COMPONENT
3 PROPERTY
  • Second segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LN" or "LO"
  • Second segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LX" or "OLX" (with expansions)
  • MRSAT.ATN = LOINC_PROPERTY
4 TIME_ASPCT
  • Third segment of colon-separated fully-specifie name, MRCONSO.STR, TTY = "LN" or "LO"
  • Third segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LX" or "OLX" (with expansions)
  • MRSAT.ATN = LOINC_TIME_ASPECT
5 SYSTEM
  • Fourth segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LN" or "LO"
  • Fourth segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LX" or "OLX" (with expansions)
  • First subfield: MRCONSO.STR, TTY = "LS" (with expansions)
  • MRSAT.ATN = LOINC_SYSTEM
6 SCALE_TYP
  • Fifth segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LN" or "LO"
  • Fifth segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LX" or "OLX" (with expansions)
  • MRSAT.ATN = LOINC_SCALE_TYP
7 METHOD_TYP
  • Sixth segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LN" or "LO"
  • Sixth segment of colon-separated fully-specified name, MRCONSO.STR, TTY = "LX" or "OLX" (with expansions)
  • MRSAT.ATN = LOINC_METHOD_TYP
8 CLASS Arbitrary classification of the terms for grouping related observations together. See Table 32 in the LOINC Users' Guide for values.
  • MRCONSO.STR, TTY = "HS"
  • MRCONSO.STR, TTY = "HC" (with expansions)
  • MRSAT.ATN = "LCL"
  • Used to build hierarchy
9 VersionLastChanged The LOINC version number in which the record has last changed. MRSAT.ATN = "VERSION_LAST_CHANGED"
10 CHNG_TYPE Change Type Code: "DEL" = delete (deprecate); "ADD" = add; "NAM" = change to Analyte/Component (field #2); "MAJ" = change to name field other than #2 (#3 - #7); "MIN" = change to field other than name; "UND" = undelete MRSAT.ATN = "LCT"
11 DefinitionDescription Narrative text that describes the LOINC term MRSAT.ATN = "SOS"
12 STATUS Status
Valid values are:
ACTIVE
DEPRECATED
DISCOURAGED
TRIAL
  • For records with STATUS = "DEPRECATED", an obsolete TTY is assigned, and MRCONSO.SUPPRESS = "O"
  • MRSAT.ATN = "LCS"
13 CONSUMER_NAME Consumer-friendly name for this term. Content is experimental (beta). MRSAT.ATN = "CONSUMER_NAME"
14 CLASSTYPE 1 = Laboratory; 2 = Clinical class; 3 = Claims attachments; 4=Surveys
  • MRCONSO.STR, TTY = "HC"
  • MRCONSO.STR, TTY = "HS" (with expansions)
  • MRSAT.ATN = "LCN"
  • Used to build hierarchy
15 FORMULA Regression equation details MRSAT.ATN = "LFO"
16 EXMPL_ANSWERS Examples of valid answers MRSAT.ATN = "LEA"
17
SURVEY_QUEST_TEXT Question from survey instrument MRSAT.ATN = "LQT"
18 SURVEY_QUEST_SRC Name of survey instrument and item/question number MRSAT.ATN = "LQS"
19 UNITSREQUIRED Y/N indicates whether units are required for OBX segment in a HIPAA attachment MRSAT.ATN = "LUR"
20 RELATEDNAMES2 Synonyms for each part of the fully-specified LOINC name (component, property, time, system, scale, method) MRSAT.ATN = "LRN2"
21 SHORTNAME Concatenation of the fully-specified LOINC name MRCONSO.STR, TTY = "OSN", "OOSN"
22 ORDER_OBS Defines term as an order only, observation only, both, or Subset MRSAT.ATN = "LOR"
23 HL7_FIELD_SUBFIELD_ID Indicates that the content should be delivered in the named field/subfield of the HL7 message. MRSAT.ATN = "HL7_FIELD_SUBFIELD_ID"
24 EXTERNAL_COPYRIGHT_NOTICE External copyright holder information MRSAT.ATN = "COPYRIGHT"
25
EXAMPLE_UNITS Indicates representative units MRSAT.ATN = "EXAMPLE_UNITS"
26 LONG_COMMON_NAME Readable version of LOINC term MRCONSO.STR, TTY = "LC" or "OLC"
27 EXAMPLE_UCUM_UNITS Example units of measure expressed as UCUM units MRSAT.ATN = "EXAMPLE_UCUM_UNITS"
28 STATUS_REASON Classification of the reason for concept status. This field will be Null for ACTIVE concepts, and optionally populated for terms in other status where the reason is clear. DEPRECATED or DISCOURAGED terms may take values of: AMBIGUOUS, DUPLICATE, or ERRONEOUS MRSAT.ATN = "STATUS_REASON"
29 STATUS_TEXT Explanation of concept status in narrative text. This field will be Null for ACTIVE concepts, and optionally populated for terms in other status. MRSAT.ATN = "STATUS_TEXT"
30 CHANGE_REASON_PUBLIC Detailed explanation about special changes to the term over time. MRSAT.ATN = "CHANGE_REASON_PUBLIC"
31 COMMON_TEST_RANK Numeric ranking of approximately 2,000 common tests performed by hospitals. MRSAT.ATN = "COMMON_TEST_RANK"
32
COMMON_ORDER_RANK Ranking of approximately 300 common orders performed by laboratories in the USA. MRSAT.ATN = "COMMON_ORDER_RANK"
33 COMMON_SI_TEST_RANK Corresponding SI terms for 2000 common tests performed by laboratories in USA. MRSAT.ATN = "COMMON_SI_TEST_RANK"
34 HL7_ATTACHMENT_STRUCTURE Valid values: STRUCTURED or UNSTRUCTURED. STRUCTURED terms are the allowed document type codes in the Consolidated CDA Implementation guide. UNSTRUCTURED terms are based on the PIUC guide. MRSAT.ATN = "HL7_ATTACHMENT_STRUCTURE"
35 EXTERNAL_COPYRIGHT_LINK Used for terms with an additional third party copyright. The field is populated with the COPYRIGHT_ID from SourceOrganization.csv.
MRSAT.ATN = "EXTERNAL_COPYRIGHT_LINK"
36 PanelType Describes a panel as a "Convenience group", "Organizer", or "Panel'. MRSAT.ATN = "PANEL_TYPE"
37 AskAtOrderEntry List of LOINC codes that represent optional Ask at Order Entry (AOE) observations. MRSAT.ATN = "ASK_AT_ORDER_ENTRY"
38 AssociatedObservations List of LOINC codes that represent option associated observation(s). MRSAT.ATN = "ASSOC_OBSERVATIONS"
39 VersionFirstReleased LOINC version number in which the record was first released. For oldest records where the version released number is not known, this field will be null. MRSAT.ATN = "VERSION_FIRST_RELEASED"
40 ValidHL7AttachmentRequest A value of 'Y' indicates that the LOINC code can be sent by a payer as part of an HL7 attachment request for additional information. MRSAT.ATN = "HL7_ATTACHMENT_REQUEST"
41 DisplayName Clinician friendly name. Algorithmically created. MRCONSO.STR, TTY = "DN"

file: MapTo.csv

# Field Representation
1 LOINC Obsolete LNC code.
Used to create relationships between "LO" and "LN" atoms.
The REL= RQ;
The RELA=mapped_from/mapped_to.
2 MAP_TO Current LNC code.
3 COMMENT Rationale for using the recommended replacement term.

file: ComponentHierarchyBySystem.csv

# Field Representation
1 PATH_TO_ROOT Used to create the hierarchy tree under the " LOINCPARTS" concept
2 SEQUENCE Not used
3 IMMEDIATE_PARENT Not used
4 CODE The identifier of the "child" concept; all end nodes are LOINC IDs; ancestors are LOINC PARTs
5 CODE_TEXT Not used

file: Part.csv

# Field Representation
1 PartNumber MRCONSO.CODE, SCUI
2 PartTypeName Values are: ADJUSTMENT, CHALLENGE, CLASS,
COMPONENT, COUNT, DIVISORS, FRAGMENTS FOR SYNONYMS,
METHOD, MULTI-AXIAL, MULTIPART, PROPERTY, QUOTIENTS,
SCALE, SUFFIX, SUPER SYSTEM, SUPERSYSTEMMULTI-AXIAL,
SYSTEM, TIME, TIME MODIFIER.
Used to create relationships between LOINC PARTS and LOINC IDs and value for ATN = PART_TYPE.
3 PartName MRCONSO.STR, TTY = "LPN'
4 PartDisplayName MRCONSO.STR, TTY = "LPDN"; MRSAT.ATN = "SOS"; ATV = PartTypeName:PartDisplayName
5 Status Not used

file: LoincPartLink_Primary.csv and LoincPartLink_Supplementary.csv

# Field Description Representation
1 LoincNumber A relationship (STYPE = "SCUI") is created between the LoincNumber and the PartNumber (field3).
The REL = "RO";
The RELA is assigned based on the PartTypeName (field 6) as follows:

PART_TYPE RELA/inverse_RELA
ADJUSTMENT has_adjustment adjustment_of
CHALLENGE has_challenge challenge_of
CLASS has_class class_of
COMPONENT has_component component_of
COUNT has_count count_of
DIVISORS has_divisor divisor_of
FRAGMENTS FOR SYNONYMS has_fragments_for_synonyms fragments_for_synonyms_of
METHOD has_method method_of
MULTIPART has_multipart multipart_of
PROPERTY has_property property_of
QUOTIENTS has_quotient quotient_of
SCALE has_scale scale_of
SUFFIX has_suffix suffix_of
SUPERSYSTEM has_supersystem supersystem_of
SYSTEM has_system system_of
TIME has_time_aspect time_aspect_of
TIME MONITOR has_time_monitor time_monitor_of

Note: Some PART TYPEs (e.g., "MULTI-AXIAL" and "SUPERSYSTEMMULTI-AXIAL"
may not appear in the Part.csv file, therefore, no relationships are created for these PART TYPE values.

2 LongCommonName Not used
3 PartNUmber A relationship (STYPE = "SCUI") is created between the LoincNumber (field 1) and the PartNumber.
4 PartName Not used
5 PartCodeSystem Not used
6 PartTypeName Used to assign the RELA
7 LinkTypeName Not used
8 Property Not used

file: PanelsAndForms.csv

# Field Representation
1 ParentId Not used
2 ParentLoinc Used as id_1 in relationships; RELA = member_of/has_member; REL = RN
3 ParentName Not used
4 ID Not used
5 SEQUENCE Not used
6 Loinc Used as id_2 in relationships; RELA = member_of/has_member; REL = RN
7 LoincName Not used
8 DisplayNameForForm Not used
9 ObservationRequiredInPanel Not used
10-31 ObservationIdInForm... Not used

file: LoincAnswerListLink.csv

# Field Representation
1 LoincNumber Relationship created between Loinc concept code and AnswerList.csv.AnswerStringID; RELA = has_answer/answer_to
2 LongCommonName N/A
3 AnswerListId MRSAT.ATN = ANSWER_LIST_ID (Join field to AnswerList.csv)
4 AnswerListName MRSAT.ATN = ANSWER_LIST_NAME
5 AnswerListLinkType N/A
6 ApplicableContext N/A

file: AnswerList.csv

# Field Representation
1 AnswerListId MRSAT.ATN = ANSWER_LIST_ID (Join field to LoincAnswerListLink.csv)
2 AnswerListName MRSAT.ATN = ANSWER_LIST_NAME
3 AnswerListOID MRSAT.ATN = ANSWER_LIST_OID
4 ExtDefinedYN Not used
5 ExtDefinedAnswerListCodeSystem Not used
6 ExtDefinedAnswerListLink Not used
7 AnswerStringId Relationship created between AnswerStringID and AnswerListLink.LoincNumber; MRCONSO.CODE, SCUI for TTY = LA
8 LocalAnswerCode MRSAT.ATN = ANSWER_CODE
9 LocalAnswerCodeSystem MRSAT.ATN = ANSWER_CODE_SYSTEM
10 SequenceNumber MRSAT.ATN = SEQ_NO
11 DisplayText MRCONSO.STR; TTY = LA; CODE = AnswerStringId
12 ExtCodeId Not used
13 ExtCodeDisplayName Not used
14 ExtCodeSystem Not used
15 ExtCodeSystemVersion Not used
16 ExtCodeSystemCopyrightNotice Not used
17 SubsequentTextPrompt MRSAT.ATN=SUBSEQUENT_TEXT_PROMPT
18 Description MRSAT.ATN=DEFINITION
19 Score MRSAT.ATN=LOINC_SCORE

file: LoincUniversalLabOrdersValueSet.csv

# Field Representation
1 LOINC_NUM LOINC codes included in this file have MRSAT.ATN = UNIVERSAL_LAB_ORDERS_VALUE_SET with MRSAT.ATV = TRUE
2 LONG_COMMON_NAME Not directly processed
3 ORDER_OBS Redundant to ORDER_OBS attribute in Loinc.csv (represented as MRSAT.ATN = LOR)

file:LoincIeeeMedicalDeviceCodeMappingTable.csv

# Field Representation
1 LOINC_NUM Code/SCUI
2 LOINC_LONG_COMMON_NAME Not used
3 IEEE_CF_CODE10 MRSAT.ATN=IEEE_CF_CODE10
4 IEEE_REFID MRSAT.ATN=IEEE_REFID
5 EQUIVALENCE MRSAT.ATN=EQUIVALENCE

file:LoincRsnaRadiologyPlaybook.csv

# Field Representation
1 LoincNumber A relationship is created between the LoincNumber and the PartNumber
2 LongCommonName Not used
3 PartNumber A relationship is created between the LoincNumber and the PartNumber
4 PartTypeName Used to identify the RELA
5 PartName Part name; MRCONSO.STR.TTY=LPN
6 PartSequenceOrder MRSAT.ATN=PART_SEQ_ORDER
7 RID MRSAT.ATN=RID
8 PreferredName MRSAT.ATN=RADLEX_PREF_NAME
9 RPID MRSAT.ATN=RPID
10 LongName MRSAT.ATN=RADLEX_PLAYBOOK_LONG_NAME

file: ImagingDocumentCodes.csv

# Field Representation
1 LOINC_NUM Code; MRSAT.ATN = IMAGING_DOCUMENT_VALUE_SET, MRSAT.ATV = TRUE
2 LOINC_LONG_COMMON_NAME Not used

file: ConsumerName.csv

# Field Representation
1 LoincNumber Code
2 ConsumerName MRSAT.ATN = CONSUMER_NAME

file: Group.csv

# Field Representation
1 ParentGroupId Relationship created between the ParentGroupId and the GroupID. MRREL.RELA = has_parent_group/parent_group_of
2 GroupId Code, SCUI
3 Group MRCONS.STR
4 Archetype Relationship created between the GroupId and its Archetype. MRREL.RELA = has_archetype/archetype_of
5 Status Used in determining the TTY (LG or OLG) and in creating MRSAT.ATN = STATUS. Valid values: Active, Inactive, Deprecated.
6 VersionFirstReleased Not populated

file: GroupLoincTerms.csv

# Field Representation
1 Category MRSAT.ATN = CATEGORY. Linked to the rel_id of the 'has_loinc_number/loinc_umber_of' relationship.
2 GroupId Used with MRREL.RELA = has_archetype/archetype_of and MRREL.RELA = has_loinc_number/loinc_number_of
3 Archetype Relationship created between the GroupId and its Archetype. MRREL.RELA = has_archetype/archetype_of
4 LoincNumber Relationship created between the GroupId and its LoincNumber. MRREL.RELA = has_loinc_number/loinc_number_of
5 LongCommonName Not used

file: GroupAttributes.csv

# Field Representation
1 ParentGroupId Not used
2 GroupId MRSAT.CODE
3 Type MRSAT.ATN. Valid values: MOLECULAR_WEIGHT_OF_ANALYTE, DESCRIPTION, USAGE_NOTES
4 Value MRSAT.ATV

file: ParentGroup.csv

# Field Representation
1 ParentGroupId MRCONSO.CODE, SCUI
2 ParentGroup MRCONSO.STR
3 STATUS Used to determine MRCONSO.TTY. MRSAT.ATN = STATUS. Valid values: Active, Inactive, Deprecated

file: ParentGroupAttributes.csv

# Field Representation
1 ParentGroupId MRSAT.CODE
2 Type MRSAT.ATN. Valid values: MOLECULAR_WEIGHT_OF_ANALYTE, DESCRIPTION, USAGE_NOTES
3 Value MRSAT.ATV