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Common LOINC Laboratory Observation Codes

We created an empirically-based list of the most common LOINC result codes for laboratories, practices, researchers, and others who wish to map their laboratory test codes to universal LOINC codes. Knowing that relatively few codes account for much of the result volume, we think that Top 2000+ list will be an excellent starter set. This list contains 2017 most commonly reported LOINC codes that represent about 98% of the test volume carried by three large organizations that mapped all of their laboratory tests to LOINC codes.

To jump start your mapping effort, we've written a Mapper's Guide to the Top 2000+ Lab Tests with a wealth of advice and guidance about which codes to choose for a given purpose.

LOINC Top 2000+ Lab Observations and Mapper's Guide

• LOINC Mapper's Guide to the Top 2000+ Lab Observations - Introduction to Version 1.0 (pdf)
  File Version: Top 2000+ Lab Observations Introduction 1.0 | File type: application/pdf | Release Date: 2011-05-31
  File Description: Background document describing the origins, development, and organization of the LONIC Mapper's Guide to the Top 2000+ Lab Observations.
  
• LOINC Mapper's Guide to the Top 2000+ Lab Observations - Version 1.0a (pdf)
  File Version: LOINC Mapper's Guide to the Top 2000+ Lab Observations 1.0 | File type: application/pdf | Release Date: 2011-06-01
  File Description: Document containing mapping guidance for the LOINC Top 2000+ Lab Observations.
  OID: 1.3.6.1.4.1.12009.10.2.3
  
• LOINC Mapper's Guide to the Top 2000+ Lab Observations - Version 1.0a (xlsx)
  File Version: LOINC Mapper's Guide to the Top 2000+ Lab Observations 1.0 | File type: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet | Release Date: 2010-06-01
  File Description: Document containing mapping guidance for the LOINC Top 2000+ Lab Observations. Requires a loinc.org account.
  OID: 1.3.6.1.4.1.12009.10.2.3
  
• LOINC Top 2000+ Lab Observations - Version 1.0 (csv)
  File Version: Top 2000+ Lab Observations 1.0 | File type: text/comma-separated-values  | Release Date: 2010-05-31
  File Description: The list of LOINC Top 2000+ Lab Observations in a simple CSV file. Does NOT contain mapping guidance.
  OID: 1.3.6.1.4.1.12009.10.2.3
  

Notes about Version 1.0a: This version contains a couple of corrections for UCUM units. The rest of the content is unchanged from version 1.0 (2010-05-31)

Common Result Codes in LOINC and RELMA

The Top 2000+ LOINC terms have their relative rank stored in the COMMON_TEST_RANK field of the main LOINC table. Starting with RELMA version 5.3, the program's "common lab tests only" filter will limits searches to only return codes in this common test list.

Background Reading

• Vreeman DJ, Finnell JT, Overhage JM. A Rationale for Parsimonious Laboratory Term Mapping by Frequency. Proc AMIA Symp. 2007;771-775.

Value set of universal laboratory order codes from LOINC

This value set defines a collection of universal laboratory order codes for use by developers of order entry systems that deliver them in HL7 messages to laboratories, where they could be understood and fulfilled. This value set is designed to cover greater than 95% of the test ordering volume in the US, and was developed with both empirical and consensus-driven approaches. This list is referenced by the HITSP C80 Clinical Document and Messaging Terminology Construct in Table 2-96 "Laboratory Order Value Set" where it states that it "should be considered a minimum 'starter' set" and "does not attempt to include all possible LOINC codes" or all possible lab orders.

Comments and suggestions are welcome at commontestsandorders@mail.nih.gov

Value Set

• Common Lab Orders Value Set - Preface to Version 1.2 (pdf)
  File Version: Common Lab Orders Preface 1.2 | File type: application/pdf | Release Date: 2011-06-03
• Common Lab Orders Value Set - Version 1.2 (pdf)
  File Version: Common Lab Orders 1.2 with Preface | File type: application/pdf | Release Date: 2011-06-03
  OID: 1.3.6.1.4.1.12009.10.2.2
• Common Lab Orders Value Set - Version 1.2 (xlsx) or if you prefer (xls)
  File Version: Common Lab Orders 1.2 | File type:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet  | Release Date: 2011-06-03
  OID: 1.3.6.1.4.1.12009.10.2.2

HITSP C80

• HITSP C80 - Clinical Document and Message Terminology Component
  Table 2-96 "Laboratory Order Value Set" reference to the LOINC Common Lab Orders value set
  

Example UCUM codes for units of measure in electronic messages

This is a draft enumeration of The Unified Code for Units of Measure (UCUM), designed to make it clear what the UCUM syntax would produce for specific unit patterns in electronic communication. This early version, composed in a relatively short time frame, is based on content provided by Intermountain Healthcare, from a National Library of Medicine and Regenstrief Institute project that is analyzing raw units from more than 23 laboratory sources and their translation to UCUM and from the HL7 table of units. In this version we have not included all of the content from all of these sources. Specifically for this version, we excluded units for which we could not quickly find definitions or clear patterns of usage, units of measure that we believed would only be used in pharmacy dispensing, and units used for purely clinical reporting (e.g. cigarette pack-years). We have included most of the pure metric units that were in the source table whether they apply directly to the laboratory or not because they will be generally useful and because we could not always be sure what should be excluded.

More detail about the process used to generate this table is given in the Preface.

Table of Example UCUM Codes for Electronic Messaging

• Table of Example UCUM Codes for Electronic Messaging - Preface to Version 1.1 (pdf)
  File Version: Table of Example UCUM Codes for Electronic Messaging Preface 1.1 | File type: application/pdf | Release Date: 2011-10-04
• Table of Example UCUM Codes for Electronic Messaging - Version 1.1 (pdf)
  File Version: Table of Example UCUM Codes for Electronic Messaging 1.1 | File type: application/pdf | Release Date: 2011-10-04
• Table of Example UCUM Codes for Electronic Messaging - Version 1.1 (xlsx)
  File Version: Table of Example UCUM Codes for Electronic Messaging 1.1 | File type:application/vnd.openxmlformats-officedocument.spreadsheetml.sheet | Release Date: 2011-10-04