Parts are building blocks (“attributes”) that are combined to make LOINC terms

LOINC Parts are coded representations of the attribute values that combine to create a LOINC term. LOINC Parts support the translation of LOINC terms into other languages, easy linking of synonyms across many terms, the creation of hierarchies to group related LOINC terms, and several other functions.

The LOINC Parts and Part hierarchies are only intended to be constituents of and/or organize LOINC terms. As described in the LOINC license, they are not intended for use as a “standalone” terminology apart from LOINC terms.

Furthermore, LOINC Parts and Part hierarchies are not strictly managed under the same policies (e.g., concept orientation, concept permanence) as are LOINC terms.

For more information regarding LOINC Parts, see Section 9.3 ("LOINC Parts and Part hierarchies") of the LOINC Users' Guide.

TIP Part codes have a prefix of LP

File Contents

See descriptions of the pertinent files below.

Download

LOINC Part File
Version: 5.3
Released: 2021-08-23
Size: 17 MB (ZIP)

  • Loinc_2.71_PartFile_5.3
  • LoincPartLinkEnrichmentReleaseNotes.pdf
  • LoincPartLink_Primary.csv
  • LoincPartLink_Supplementary.csv
  • LoincReleaseNotes.pdf
  • Loinc_2.71_License_5.2.txt
  • Part.csv
  • PartFileReadMe.txt
  • PartRelatedCodeMapping.csv

API Access

LOINC Parts can be retrieved as part of the CodeSystem resource of LOINC's FHIR Terminology Server. You can use the $lookup operation to get details on the specified Part code. You can also focus your request to return an individual property (or numerous properties) for the Part.

See our documentation for more information on how to use the Terminology Server including example requests.

File Descriptions

Part.csv

This file contains all of the primary LOINC Parts that are associated with any of the LOINC terms included in the current LOINC release. The types of Parts included in this file fall into five major categories. For definitions of each Part in the first four categories, see the chapter of the LOINC Users' Guide indicated below for each category.

  1. Six major Parts that define a LOINC term (Component, Property, Time Aspect, System, Scale, and Method)
    • Section 2 "Major Parts of a test or observation name"
  2. Additional Parts that contribute to the term, such as the Divisor, Challenge, and Class
    • Section 2 "Major Parts of a test or observation name"
  3. Parts that define document terms within the Document Ontology
    • Section 6 "LOINC Document Ontology"
  4. Parts that define radiology terms according to the LOINC/RSNA Radiology Playbook unified model
    • LOINC Users' Guide Annex ("LOINC/RSNA Radiology Playbook User Guide")
  5. Parts that are used in the LoincPartLink file but are not part of LOINC's official semantic model. These Parts may later be used to link to external sources or coding systems. Currently the only Part type that falls in this category is Gene.

Parts that were previously released but that are no longer used to define any published LOINC term are not included in this file. However, Parts associated with Deprecated LOINC terms ARE included in this file, because those terms continue to be released.

You will notice that in some cases, especially in the radiology domain, Parts may appear incomplete, such as LP234153-7, which is the Component (Views AP + odontoid) + (View lateral. This Part, and others like it, are not erroneous. Rather, they are necessary for our internal processes that build the LOINC Long Common Name from the individual parts.

LoincPartLink_Primary.csv and LoincPartLink_Supplementary.csv

These file contains every LOINC term included in the current LOINC release and the Parts that it is linked to. Each term to Part linkage has one of the following link types:

  1. "Primary" - the key Parts that make up the five (or optionally six) main attributes of the LOINC Fully Specified Name;  
  2. "Search" - Parts that are only linked to a given term in order to facilitate efficient searching and location of that term (note that parts that have a "Search" type link to one LOINC term may have a "Primary" link to another LOINC term); 
  3. "DocumentOntology" - the Parts that define that term within the Document Ontology; 
  4. "Radiology" - the Parts that define that term within the LOINC/RSNA Radiology Playbook unified model;
  5. "DetailedModel" - the Parts that comprise all of the more detailed compositional subparts, such as Challenge and Super System, that create a fully defined term according to the LOINC semantic model;
  6. "SyntaxEnhancement" - the Parts that represent useful pieces of the LOINC Component, such as Suffix and Divisor, that are not officially part of the semantic model;
  7. "SemanticEnhancement" - the Parts linked to a LOINC term that are part of the LOINC term name but not officially part of the semantic model and are used to link terms to external sources or coding systems, e.g., Gene; and
  8. "Metadata" - Parts that define accessory term attributes that are coded but not part of the LOINC term name (e.g., Class).

Note that Document Ontology and Radiology terms have "Primary" Part links (Component, Property, etc.) as well as a set of "DocumentOntology" or "Radiology" Part links, respectively. They may additionally have "Search" links. They do not have "DetailedModel" links because the general detailed model is superseded by the Document Ontology and Radiology models.

PartRelatedCodeMapping.csv

This file contains mappings between LOINC Parts and concepts in external coding systems, such as SNOMED CT and RadLex. Only the subset of LOINC Parts that are mapped to an external concept are included in this file. The MapType and ContentOrigin fields are only valued for a subset of mappings. For the SNOMED CT mappings, the values in both of these fields are based on similar content in the LOINC/SNOMED CT Map Set published jointly by Regenstrief Institute and SNOMED International.

LOINC Part Link Enrichment

This PDF explains in detail the changes made as part of the Version 3.0 Alpha 1 release of the Part File.

Example

The following tables show how the LOINC term and its corresponding Parts are represented in the three CSV files available within this artifact.

42272-5

Fully-Specified Name

Views PA + lateral:Find:Pt:Chest:Doc:XR

Excerpt from LoincPartLink.csv

LoincNumber LongCommonName PartNumber PartName PartCodeSystem PartTypeName LinkTypeName Property
42272-5 XR Chest PA and Lateral LP221266-2 Views PA + lateral http://loinc.org COMPONENT Primary http://loinc.org/property/COMPONENT
42272-5 XR Chest PA and Lateral LP6813-2 Find http://loinc.org PROPERTY Primary http://loinc.org/property/PROPERTY
42272-5 XR Chest PA and Lateral LP6960-1 Pt http://loinc.org TIME Primary http://loinc.org/property/TIME_ASPCT
42272-5 XR Chest PA and Lateral LP7138-3 Chest http://loinc.org SYSTEM Primary http://loinc.org/property/SYSTEM
42272-5 XR Chest PA and Lateral LP32888-7 Doc http://loinc.org SCALE Primary http://loinc.org/property/SCALE_TYP
42272-5 XR Chest PA and Lateral LP21166-1 XR http://loinc.org METHOD Primary http://loinc.org/property/METHOD_TYP
42272-5 XR Chest PA and Lateral LP221266-2 Views PA + lateral http://loinc.org COMPONENT SyntaxEnhancement http://loinc.org/property/analyte-core
42272-5 XR Chest PA and Lateral LP220588-0 PA http://loinc.org Rad.View.View Type Radiology http://loinc.org/property/rad-view-view-type
42272-5 XR Chest PA and Lateral LP199962-4 Chest http://loinc.org Rad.Anatomic Location.Region Imaged Radiology http://loinc.org/property/rad-anatomic-location-region-imaged
42272-5 XR Chest PA and Lateral LP220572-4 lateral http://loinc.org Rad.View.View Type Radiology http://loinc.org/property/rad-view-view-type
42272-5 XR Chest PA and Lateral LP212285-3 XR http://loinc.org Rad.Modality.Modality Type Radiology http://loinc.org/property/rad-modality-type
42272-5 XR Chest PA and Lateral LP221404-9 Views http://loinc.org Rad.View.Aggregation Radiology http://loinc.org/property/rad-view-aggregation
42272-5 XR Chest PA and Lateral LP28726-5 Views http://loinc.org COMPONENT Search http://loinc.org/property/search
42272-5 XR Chest PA and Lateral LP33431-5 Views PA & lateral http://loinc.org COMPONENT Search http://loinc.org/property/search
42272-5 XR Chest PA and Lateral LP34109-6 Views+PA http://loinc.org COMPONENT Search http://loinc.org/property/search
42272-5 XR Chest PA and Lateral LP40367-2 Views PA http://loinc.org COMPONENT Search http://loinc.org/property/search
42272-5 XR Chest PA and Lateral LP221202-7 (Views http://loinc.org COMPONENT Search http://loinc.org/property/search
42272-5 XR Chest PA and Lateral LP29684-5 RAD http://loinc.org CLASS Metadata http://loinc.org/property/CLASS

Excerpt from Part.csv

PartNumber PartTypeName PartName PartDisplayName Status
LP221266-2 COMPONENT Views PA + lateral Views PA and lateral ACTIVE
LP6813-2 PROPERTY Find Finding ACTIVE
LP6960-1 TIME Pt Point in time (spot) ACTIVE
LP7138-3 SYSTEM Chest Chest ACTIVE
LP32888-7 SCALE Doc Doc ACTIVE
LP21166-1 METHOD XR X-ray ACTIVE
LP221266-2 COMPONENT Views PA + lateral Views PA and lateral ACTIVE
LP220588-0 Rad.View.View Type PA PA ACTIVE
LP199962-4 Rad.Anatomic Location.Region Imaged Chest Chest ACTIVE
LP220572-4 Rad.View.View Type lateral lateral ACTIVE
LP212285-3 Rad.Modality.Modality Type XR XR ACTIVE
LP221404-9 Rad.View.Aggregation Views Views ACTIVE
LP28726-5 COMPONENT Views Views ACTIVE
LP33431-5 COMPONENT Views PA & lateral Views PA and lateral ACTIVE
LP34109-6 COMPONENT Views+PA Views and PA ACTIVE
LP40367-2 COMPONENT Views PA Views PA ACTIVE
LP221202-7 COMPONENT (Views (Views ACTIVE
LP29684-5 CLASS RAD Radiology ACTIVE

Excerpt from PartRelatedCodeMapping.csv

PartNumber PartName PartTypeName ExtCodeId ExtCodeDisplayName ExtCodeSystem MapType ContentOrigin ExtCode
SystemVersion
ExtCode
System
Copyright
Notice
LP220588-0 PA Rad.View.View Type RID43594 PA view http://www.radlex.org 3.15
LP199962-4 Chest Rad.Anatomic Location.Region Imaged RID1243 Thorax http://www.radlex.org 3.15
LP220572-4 lateral Rad.View.View Type RID43591 lateral view http://www.radlex.org 3.15
LP212285-3 XR Rad.Modality.Modality Type RID10345 projection radiography http://www.radlex.org 3.15
LP221404-9 Views Rad.View.Aggregation RID49567 multiple views http://www.radlex.org 3.15