FDA issued Final Guidance on Applying Human Factors and Usability Engineering to Medical Devices

With QMSR alignment in February and issuing the Content of Human Factors Information in Medical Device Marketing Submissions guidance document in May, FDA has had a busy year. This guidance replaces the 2016 guidance that industry has been relying on for ten years. Let's go over what changed:

The 2026 revision updates the regulatory framework around human factors to reflect the QMSR and ISO 13485:2016 rather than the old 21 CFR 820.30 design control structure. It also shifts documentation terminology from the old design history file concept toward the design and development file language used under ISO 13485. If you have completed your QMSR alignment, this change should not affect you. Related terminology was also modernized to better align with ISO 14971. The guidance now uses risk control measures more consistently in place of older phrasing such as risk management measures or strategies. The definitions section was expanded as well. FDA now formally defines terms that were not explicitly defined in the 2016 guidance, including normal use, residual risk, serious harm, serious injury, use environment, and use-related risk analysis (URRA).

Standards references were updated to current editions, including IEC 62366-1:2015+A1:2020 and ISO 14971:2019. No big surprised here. Again, if you have a robust QMS, you should be updating standards used within the QMS regularly.

One of the more substantive changes is that the URRA is now a clearly defined and expected artifact. FDA formally defines the URRA and, in the marketing-submission guidance, provides an example table structure that includes the user task, possible use errors, hazardous situation, potential harm, severity, critical-task designation, risk control measures, and method used to validate those controls. I have seen many consultants crying out that Appendix A is gone which had the required structure... it has not gone, it is just contained/restructured in the Content of Human Factors Information in Medical Device Marketing Submissions guidance document. This is still needed. You are not off the hook for your URRA!

Critical-task determination is now tied more explicitly to the URRA. FDA recommends documenting the severity scale used to determine which tasks are critical, including the applicable reference when a defined severity framework is used. For modified devices, FDA also expects the manufacturer to identify which critical tasks are new or impacted by the change. For modifications, the analysis is also broader than just examining the changed component. FDA recommends evaluating the final finished device, including upstream and downstream effects on user interactions and the cumulative effects of multiple changes.

The newer guidance is somewhat more explicit about what happens after validation identifies problems. The terminology now refers to human factors revalidation where additional risk controls or design changes warrant it, rather than simply describing the activity as retesting. Note, residual-risk expectations are also more explicit in the marketing guidance. For Category 3, FDA expects a residual risk analysis, a rationale for why the implemented controls are acceptable, and a benefit-risk discussion where relevant. If residual use-related risk remains unacceptable, FDA recommends reevaluating risk controls to determine whether further reduction is possible.

There are also several smaller cleanup changes. The 2026 guidance updates sources for identifying known use problems, such as changing the recalls reference to Medical Device Recalls and Early Alerts and updating the ECRI reference.

FDA also cleaned up its wording around “summative testing.” The newer guidance avoids treating that term as automatically synonymous with FDA human factors validation because some definitions of summative testing do not contain all the elements FDA expects.

Not too many big changes if you were following best practices already; however, if might be worth taking a peek at your Human Factors, Design and Development, Design Change, and Risk Management SOPs to ensure alignment with the guidance.

FDA guidance is nonbinding, but represents FDA’s current regulatory expectations. Deviations from guidance are permissible when an alternative approach satisfies applicable statutory and regulatory requirements and is appropriately justified. That justification bit is tricky though and Polaris Biomedical strongly recommends following these guidance documents to speed up reviews or inspections.