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Logical Observation Identifiers Names and Codes for In Vitro Diagnostic Tests Guidance for Industry and Food and Drug Administration Staff June 2018

Docket Number:
Issued by:
Guidance Issuing Office
Center for Devices and Radiological Health

FDA recognizes that with the increasing implementation of electronic health records (EHR), there has been a greater demand to standardize the way that in vitro diagnostic (IVD) tests are coded. Efforts to harmonize and standardize information captured and stored in electronic healthcare systems carry important implications for public health, including expediting access to patient diagnostic information for healthcare providers, reducing burdens on laboratories for connecting new diagnostic systems to Laboratory Information Systems (LIS), and facilitating the use of healthcare information for decision support tools, in addition to many more potential uses.

Information from IVD tests form a significant proportion of all EHRs. Laboratories commonly associate a LOINC® (Logical Observation Identifiers Names and Codes; owned, developed, and curated by the Regenstrief Institute) code with each test being performed by a laboratory. For each IVD test, LOINC provides a unique numeric code associated with test attributes that identify the type of IVD test such as the component, property, time, system, scale and method. At present, LOINC is the IVD coding system that is most widely used by clinical laboratories and EHRs, and is the IVD coding standard recommended by the Office of the National Coordinator for Health Information Technology (ONC) in the U.S. Department of Health and Human Services (HHS) as an essential part of meaningful use. LOINC is a partially FDA-recognized consensus standard, where the recognition is limited to IVD tests. To review the classes of LOINC that are currently not recognized by FDA, see the FDA Recognized Consensus Standards Database Web site.

It is important to distinguish between LOINC codes and Unique Device Identifiers (UDIs). The LOINC coding system identifies the type of laboratory test being performed, and the UDI identifies a specific model/version of a regulated laboratory device made by a specific manufacturer. This guidance neither addresses nor affects the requirements related to the assignment of UDIs for regulated devices.

FDA’s guidance documents, including this guidance, do not establish legally enforceable responsibilities. Instead, guidances describe the Agency’s current thinking on a topic and should be viewed only as recommendations, unless specific regulatory or statutory requirements are cited. The use of the word “should” in Agency guidance means that something is suggested or recommended, but not required. Similarly, the use of “should not” in this guidance does not suggest or create an independent legal prohibition, but indicates a recommended practice.

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You can submit online or written comments on any guidance at any time (see 21 CFR 10.115(g)(5))

If unable to submit comments online, please mail written comments to:

Dockets Management
Food and Drug Administration
5630 Fishers Lane, Rm 1061
Rockville, MD 20852

All written comments should be identified with this document's docket number: FDA-2017-D-6982.

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