LOINC 101: A guide to the standardized vocabulary

Need a brief refresher on the basics of what LOINC® codes are and how they work? We’ve got you covered. Take a few minutes to brush up on the coding system with our LOINC 101 guide.
LOINC_Guide

Table of Contents

What is LOINC?

LOINC, which stands for Logical Observation Identifiers Names and Codes, is a system used to electronically transmit a vast amount of health data, including clinical laboratory test orders and results. Currently, there are over 179 countries that have adopted LOINC, and it is translated into 20 different languages.

Why is LOINC used?

LOINC was developed in 1994 to facilitate the exchange of laboratory results between healthcare organizations. Prior to its inception, laboratory test codes were distinct from each other and data could not be sent and received between healthcare providers.

How is LOINC maintained?

LOINC was created and is maintained by the Regenstrief Institute, an Indiana-based nonprofit healthcare research organization. LOINC updates are released twice a year, in June and December.

What do LOINC codes look like?

LOINC code descriptions contain six parts, each with a specific meaning. They are alpha-numeric and, unlike other code sets, have a more sentence-like structure.

What are those six parts?

Part 1: Component or Analyte

What is being measured, e.g., glucose, MAPT gene targeted mutation analysis.

Part 2: Property

The units of measure, or attributes, of what is being analyzed such as mass/volume, titer, or mass/day.

Part 3: Time Aspect

The time interval over which the test is performed.

Part 4: System

The specimen upon which the test is performed, for example, saliva, serum, or peritoneal fluid.

Part 5: Scale

How the test result will be expressed.

Part 6: Method

What methodology is being used to make the measurement. This is optional but often important when interpreting test results.

Code Example

Measuring Glucose in Urine LOINC 5792-7:

Fully specified name: Glucose:MCnc:PT:Urine:Qn:Teststrip

Long Common Name: Glucose [Mass/volume] in Urine by Test strip

Short Name: Glucose Ur Strip-mCnc

Display Name: Glucose Test strip (U) [Mass/Vol]

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