FDA Finalizes Risk-Based Framework for Human Factors Information in Medical Device Submissions

By Brynn Stanley

On May 29, 2026, the U.S. Food and Drug Administration (FDA) issued its final guidance, Content of Human Factors Information in Medical Device Marketing Submissions. The guidance establishes a new risk-based framework for determining what human factors engineering and usability engineering information manufacturers should include in medical device marketing submissions.

The final guidance applies to premarket notification submissions, or 510(k)s, Premarket Approval Applications, or PMAs, De Novo classification requests, and Humanitarian Device Exemption applications submitted to FDA’s Center for Devices and Radiological Health. It complements, rather than replaces, FDA’s existing guidance on Applying Human Factors and Usability Engineering to Medical Devices.

FDA will hosted a virtual town hall on July 22, 2026 to discuss the final guidance. FDA recognizes that manufacturers and the Agency may need at least 60 days to operationalize the new recommendations. For submissions already pending when the guidance was issued, and submissions received before August 1, 2026, FDA generally does not expect manufacturers to include all newly recommended information.

What Is New?

The most significant change is FDA’s creation of three Human Factors Submission Categories. Manufacturers are expected to use a decision-making framework based on the device’s use-related risk analysis, critical tasks, proposed device changes, user interface complexity, history of use, and existing risk controls.

The three categories determine the amount of human factors information FDA recommends including in a submission:

Human Factors Submission Category 1

Category 1 generally applies to modifications of previously authorized devices when there are no changes affecting the device’s:

• User interface;
• Intended users;
• Intended uses;
• Use environments;
• Training; or
• Labeling.

The submission should include a conclusion and high-level summary explaining why the modification does not affect the device’s human factors considerations. Manufacturers may reference prior human factors evaluations but generally do not need to resubmit materials FDA previously reviewed.

Human Factors Submission Category 2

Category 2 generally applies when:

• A new device has no critical tasks;
• A modified device introduces no new critical tasks and does not affect existing critical tasks; or
• Critical tasks are present or affected, but the manufacturer can provide an adequate rationale for not submitting new human factors validation testing.

The submission should include a clear, evidence-based rationale supporting the Category 2 determination. Depending on the basis for the determination, FDA recommends describing the intended users, uses, use environments, training, user interface, known use problems, and other information supporting the conclusion.

Human Factors Submission Category 3

Category 3 applies when human factors validation test data should be included in the submission. Manufacturers should submit a comprehensive human factors engineering or usability engineering report that includes the validation testing associated with critical tasks.

The guidance provides recommended report structures and sample outlines for each category. These tools should help manufacturers present information more consistently and may reduce requests for additional information during FDA review.

When Is Human Factors Validation Testing Required?

The guidance does not establish a rule that every device with a critical task requires new validation testing. Instead, manufacturers should determine whether validation test data should be submitted by evaluating several risk-based factors.

Human factors validation data are more likely to be needed when:

• The device has a complex user interface;
• The device requires programming, monitoring, maintenance, multiple connections, selections, or operational steps;
• The device type has a known history of use errors;
• A change introduces a new critical task;
• A change affects an existing critical task;
• The device introduces a novel technology or user interface;
• The intended users, indications, or use environment have changed;
• Complaint, recall, adverse event, or problem-report data identify a use-related safety signal; or
• The severity of potential harm associated with a use error has increased.

FDA specifically identifies infusion pumps as an example of a device type historically associated with known use-error concerns.

For a modified device, new validation testing may not be necessary merely because an existing critical task is affected. A manufacturer may be able to submit a rationale instead when existing risk controls remain effective. However, that rationale should be supported by objective evidence demonstrating that the risk controls continue to eliminate or appropriately reduce the use-related risk.

Manufacturers should also evaluate the final finished device as a whole, rather than evaluating only the modified feature. FDA recommends considering whether the modification may affect upstream or downstream tasks, the user’s perception or cognition, physical interactions with the device, or the number of steps needed to perform a critical task.

When the appropriate approach is unclear, FDA recommends seeking feedback through the Q-Submission Program.

Common Human Factors Submission Deficiencies

The final guidance provides a clearer roadmap for avoiding deficiencies that can delay review. Manufacturers should pay particular attention to the following areas.

Unsupported Submission Category Determinations

Simply stating that validation testing is unnecessary may not be sufficient. FDA expects the submission to identify the applicable Human Factors Submission Category and explain the basis for that determination.

For Category 2 submissions, the rationale should directly address the applicable decision point and should be supported by the use-related risk analysis and other objective evidence.

Incomplete Use-Related Risk Analyses

The use-related risk analysis should identify all relevant user tasks and distinguish critical tasks from noncritical tasks. For modified devices, the analysis should assess the complete device and consider the cumulative impact of multiple modifications.

A risk analysis limited to the feature being changed may fail to identify effects on related or downstream tasks.

Failure to Address All Elements of the User Interface

FDA’s definition of the user interface is broader than physical device controls. It may include:

• Packaging;
• Labeling;
• Instructions for use;
• Training materials;
• Displays;
• Alarms;
• Software screens;
• Device operating logic; and
• Interactions among device components.

A submission may be deficient when it evaluates the physical device but does not adequately assess changes to labeling, training, software, packaging, or other elements that influence how users interact with the device.

Insufficient Support for Leveraging Prior Testing

Manufacturers may rely on prior human factors work when appropriate, but the submission should explain why the prior evaluation remains applicable to the current device, intended users, intended uses, training, and use environments.

When a new device has the same or a similar user interface as one of the manufacturer’s own legally marketed devices, comparative analyses may help support reliance on prior information. These analyses may include task comparisons, labeling comparisons, physical comparisons, and evaluations of whether the same use-related risks remain applicable.

Inadequate Treatment of Known Use Problems

Manufacturers should address available information concerning known use-related problems, including:

• Complaints;
• Recalls;
• Adverse events;
• Medical Device Reports;
• Customer feedback;
• Literature;
• Problem reports; and
• Experience with similar legally marketed devices.

Failure to identify or meaningfully evaluate known use problems may undermine the submission’s critical-task analysis and its rationale for whether validation testing is needed.

Validation Testing That Does Not Reflect Actual Use

When validation testing is submitted, the test should represent the intended users, uses, use environments, training, and final user interface. Testing may be inadequate when it relies on unrepresentative participants, unrealistic scenarios, incomplete tasks, or device configurations that do not reflect the final finished device.

Manufacturers should also ensure that all critical tasks are appropriately evaluated and that use errors, close calls, and difficulties are analyzed rather than dismissed solely because participants ultimately completed a task.

Reliance on Labeling as the Primary Risk Control

Instructions, warnings, and training may be appropriate risk controls, but FDA generally expects manufacturers to consider whether the user interface can be redesigned to eliminate or reduce the risk before relying primarily on labeling or training.

A weak explanation of why additional design-based risk reduction is not feasible may result in questions regarding the adequacy of the manufacturer’s risk controls.

Preparing 510(k) Submissions

For a 510(k), human factors information may be relevant to FDA’s determination of whether the device is substantially equivalent to the predicate device.

Manufacturers should not assume that human factors validation testing is unnecessary simply because the device has the same intended use as the predicate. Differences in technological characteristics, user interfaces, intended users, training, or use environments may introduce new or different use-related risks.

Before submitting a 510(k), manufacturers should:

• Determine the Human Factors Submission Category early in development;
• Compare the subject device’s user interface to the predicate and other similar devices;
• Document whether differences affect critical tasks;
• Update the use-related risk analysis to reflect the final finished device;
• Identify known use problems associated with the device type and predicate;
• Determine whether existing risk controls remain effective;
• Prepare an evidence-based rationale when validation data will not be submitted; and
• Consider a Pre-Submission when the need for validation testing is uncertain.

The human factors section should be consistent with the device description, indications for use, labeling, risk management documentation, software documentation, and performance testing elsewhere in the submission.

Preparing PMAs and PMA Supplements

For a PMA, human factors information may contribute to FDA’s evaluation of whether there is a reasonable assurance that the device is safe and effective.

PMA devices are often higher risk, more complex, or associated with potentially serious consequences from use error. As a result, manufacturers should expect FDA to closely evaluate critical tasks, risk controls, validation methods, test results, and residual use-related risks.

For PMA supplements involving device modifications, manufacturers should carefully evaluate whether changes to the user interface, labeling, software, training, intended users, intended use, or use environment affect previously evaluated critical tasks.

Before submitting a PMA or PMA supplement, manufacturers should:

• Integrate human factors activities into the overall design and risk management process;
• Confirm that validation testing evaluates the final finished user interface;
• Ensure that participant populations adequately represent all intended user groups;
• Evaluate the device in representative use environments;
• Address all critical tasks and reasonably foreseeable use scenarios;
• Analyze use errors, close calls, task failures, and participant difficulties;
• Explain how residual use-related risks were evaluated and determined to be acceptable;
• Demonstrate how validation findings relate to the overall benefit-risk assessment; and
• Ensure that the human factors report is consistent with the design history and other submission sections.

Manufacturers submitting a PMA supplement should not limit the human factors evaluation to the changed component. FDA recommends assessing the modification’s potential effect on the entire device and on related tasks throughout the use process.

What Manufacturers Should Do Now

Manufacturers preparing upcoming marketing submissions should consider taking the following steps:

1. Update submission procedures. Incorporate the three Human Factors Submission Categories into regulatory and design-control procedures.
2. Review submission timelines. Confirm whether submissions planned for August 1, 2026, or later are prepared to follow the final guidance.
3. Reassess use-related risk analyses. Verify that current analyses identify all user tasks, critical tasks, known use problems, intended users, and use environments.
4. Evaluate device modifications holistically. Assess whether changes to software, labeling, packaging, training, or other interface elements affect critical tasks elsewhere in the use process.
5. Document Category 2 rationales carefully. When validation testing will not be submitted, prepare objective evidence supporting the effectiveness of existing risk controls.
6. Align submission content. Ensure consistency among human factors documentation, labeling, risk management files, design documentation, and other submission sections.
7. Use the Pre-Submission process strategically. Seek FDA feedback before completing validation testing when the submission category, test approach, participant groups, or ability to leverage prior data is uncertain.
8. Maintain complete records. Human factors information should be maintained within the quality system even when it is not included in the marketing submission.

Key Takeaway

FDA’s final guidance does not necessarily require more human factors validation testing for every device. Instead, it requires manufacturers to provide a clearer and more structured explanation of what human factors information is appropriate for the submission.

The new framework gives manufacturers greater flexibility to rely on existing evidence or submit a rationale in place of new validation testing when justified. That flexibility, however, comes with an expectation that the manufacturer’s submission category, risk analysis, critical-task determination, and supporting evidence are complete, consistent, and well documented.

How Gardner Law Can Help

Gardner Law advises medical device manufacturers on human factors strategy, design controls, use-related risk management, and preparation of 510(k), De Novo, and PMA submissions. Our team can help manufacturers determine the appropriate Human Factors Submission Category, assess whether validation testing is needed, evaluate testing protocols and reports, prepare supporting rationales, and identify potential submission deficiencies before filing. We also assist companies with Pre-Submission strategies and responses to FDA requests for additional information.