Origins of LOINC

LOINC, which stands for Logical Observation Identifiers Names and Codes, was initiated in 1994 by Clem McDonald, then an investigator at Regenstrief Institute, a non-profit medical research organization associated with Indiana University. Regenstrief organized the LOINC Committee to develop a common terminology for laboratory and clinical observations because there was a growing trend to send clinical data electronically from laboratories and other data producers to hospitals, physician's offices, and payers who use the data for clinical care and management purposes.

At the time—and still today—most laboratories and clinical services use HL7 to send their results electronically from their reporting systems to their care systems. However, the tests in these messages are identified by means of their internal, idiosyncratic code values. As a result, receiving care system cannot fully "understand" and properly file the results they receive unless they either adopt the producer's test codes (which is impossible if they receive results from multiple sources), or invest in the work to map each result producer's code system to their internal code system.

Clem J. McDonald, MD
Clem J. McDonald, MD

Here's the problem that LOINC solves:
LOINC provides universal codes and names that provide the global lingua franca for identifying tests and observations.

What LOINC is

LOINC is a common language (a set of identifiers, names, and codes) for identifying health measurements, observations, and documents.

LOINC is a rich catalog of measurements, including laboratory tests, clinical measures like vital signs and anthropomorphic measures, standardized survey instruments, and more. LOINC also contains codes for collections of these items, such as panels, forms, and documents.

LOINC enables the exchange and aggregation of clinical results for care delivery, outcomes management, and research by providing a set of universal codes and structured names to unambiguously identify things you can measure or observe.

Put another way, LOINC provides the lingua franca for interoperable data exchange.

Today, it contains concepts for everything from a serum alpha 1 antitrypsin level to a zygomatic arch x-ray report. For each concept, LOINC contains many other rich details, such as synonyms, units of measure, and carefully crafted descriptions.