FDA Says LOINC Coding of IVD Tests Is Voluntary, Not Mandatory

On June 15, the FDA issued a new guidance document clarifying the rules for laboratory coding of in vitro diagnostic tests. There are four key takeaways for IVD test makers and labs:

1. No Mandatory Lab Coding of Tests
Laboratory coding is voluntary, not mandatory. However, the FDA recommends that test makers use the Observation Identifiers Names and Codes (LOINC) for coding IVD tests.

2. No Mandatory Lab Coding of Devices
Similarly, the FDA is recommending but not requiring inclusion of LOINC codes for IVD tests in labeling of medical devices. The agency does not intend to perform premarket review of the LOINC codes that manufacturers provide to labs or other users.

3. LOINC Codes Must Be for Test’s Approved Indications
According to the guidance document, the LOINC codes the device manufacturer provides should be consistent with the particular IVD test’s FDA-cleared or approved indications for use. Dissemination of LOINC codes suggesting an unapproved or uncleared indication may be evidence that the device is adulterated and/or misbranded.

4. LOINC Code Distribution Format Neither Required nor Recommended
While declining to recommend a specific format for distribution, the agency “acknowledges” that LOINC codes may be displayed as simple text in a table format, or in structured formats such as Java Script Object Notification (JSON) or Extensible Markup Language (XML). However, the FDA “strongly encourages” use of an FDA-recognized consensus standard, e.g., the LOINC transmission document for IVDs (LIVD) standard, for communicating or disseminating the LOINC codes provided by manufacturers or others to labs or other end users.