LOINC Document Ontology

Organize your clinical documents with the LOINC Document Ontology

Inside many EHRs and clinical data warehouses it is a bit like your clothes closet — not as tidy as you'd like.

This is especially true if you're aggregating data across several sites. There's often a mishmash of note titles like Dr. Smith's Tuesday Pain Clinic, Chronic Pain Clinic, and Outpatient Pain Note.

Here's where the LOINC Document Ontology comes in

The LOINC Document Ontology is a special set of LOINC codes that are built on a framework for naming and classifying the key attributes of clinical documents. They provide consistent semantics for documents exchanged between systems for many uses.

When you link your local note titles to LOINC codes, instead of cryptic and idiosyncratic note titles, you'll have a principled set of document name attributes. With these systematic attributes, it's easy to create a logical navigation tree in your document viewer or write hyper-efficient queries that pull back all the cardiology notes or discharge summaries.

The LOINC Document Ontology provides the framework you've been missing



Organize documents in a clinical results viewer logically



Create super-powered queries using structured document properties



Build data entry templates specific to particular document types

Get the world's leading comprehensive document naming framework

The LOINC Document Ontology represents the five key attributes of clinical documents that can be understood across systems.

  • Subject Matter Domain

    e.g. Cardiology, Pediatric Cardiology, Physical Therapy

  • Role

    e.g. Physician, Nurse, Case Manager, Therapist, Patient

  • Setting

    e.g. Hospital, Outpatient, Emergency Department

  • Type of Service

    e.g. Consultation, History and Physical, Discharge Summary

  • Kind of Document

    e.g. Note, Letter, Consent


LOINC Complete

Your LOINC login is required to download. This accessory file is available within the combined LOINC file. Get more information on files included within this zip archive.

Version 2.77
Released 2024-02-27
Size 71.30 MB

Support for multiple levels of granularity

Some institutions like to have distinct documents for different provider roles (nurse, case manager, etc.). Others don't.

Some institutions like to distinguish among care settings in the document name. Others don't.

With the power of the LOINC Document Ontology, you can effectively group and organize documents coming from disparate sites and different preferences into a systematic framework. Organize the chaos, but retain the underlying detail.

Used worldwide in HL7's CDA standard

The HL7 Clinical Document Architecture (CDA) standard specifies that the clinicalDocument.code for any CDA document should come from LOINC. Implementation guides like the Consolidated CDA Templates for Clinical Notes that are part of the Meaningful Use regulations require LOINC codes to identify the document types. LOINC codes from the Document Ontology are required in the C-CDA value sets for documents such as consult notes, discharge summaries, progress notes, procedure notes, op notes, and more.

Browse the current version of the LOINC Document Ontology

See the attribute values and organization of each axis.

Document Ontology

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