An FDA human factors engineering report (HFE/UE report) is the document that tells the complete story of your use-safety work — and FDA's guidance lays out its expected structure in eight sections, from intended users through the final residual-risk conclusion. Teams that treat it as a write-up of the summative study alone get additional-information requests; the report is supposed to summarize the entire human factors program.
This is the working structure, section by section, based on FDA's 2016 guidance Applying Human Factors and Usability Engineering to Medical Devices.
Define who uses the device (every distinct user group), what they use it for, where (home, clinical, ambulance — with the environmental conditions that matter: lighting, noise, interruptions), and what training they'll realistically receive. Everything downstream — risk analysis, user groups, summative design — must trace back to this section, so write it precisely.
The complete user interface: hardware controls, displays, alarms, packaging, labeling, and the instructions for use. Include images and a description of the operational sequence — how a user moves through setup, use, and maintenance. The IFU is part of the user interface; FDA evaluates it as such.
What's known about use problems with previous models or similar devices: complaint data, MDRs, recalls, literature, and post-market data for comparable products. If you found nothing, document the search. This section demonstrates you looked before you designed.
The analytical core of the report: every use scenario and task, the potential use errors for each, the resulting hazards, and the severity of potential harm. The URRA is a living document throughout development — every formative round should have updated it. In the report, present the final version and make the link from each identified risk to its mitigation explicit.
Critical tasks are those where a use error would or could cause serious harm. List them, state how they were derived from the URRA, and describe how the user interface design addresses each. This list defines the scope of your validation study — FDA will check that every critical task was evaluated in the summative.
For each formative: objectives, method, participants, key findings, and — most importantly — what changed as a result. This section proves the iterative process worked. A formative summary with no resulting design or labeling changes reads as box-checking.
The full account: participant demographics by user group (15 minimum per distinct group, US-representative), training provided, test environment, tasks evaluated, performance results, and a root-cause analysis of every use error, close call, and difficulty on critical tasks. Subjective data (post-task interviews) supplements but never replaces performance data.
The closing argument: the device has been found safe and effective for the intended users, uses, and environments — with any residual use-related risks identified, analyzed, and justified as outweighed by benefits and as reduced as far as practicable. This is the sentence the entire report exists to support.
It's expected whenever the device has critical tasks — where use error could cause serious harm. Many 510(k)s, De Novos, and PMAs include one; FDA's guidance and device-specific guidances indicate when human factors data is needed.
Commonly 40–120 pages plus appendices (protocol, data tables, IFU), depending on device complexity and program length.
No — summarizing formative evaluations and the changes they drove is an expected section.
The summative report documents one study; the HFE/UE report wraps the entire human factors program around it, from intended users through residual risk.
Usability House provides the facility, recruitment, and study logistics behind submission-grade human factors programs. If your consultancy or internal team needs labs and participants for the studies this report describes, we can quote within 24 hours.
We supply the labs, participants, and logistics. Tell us what your submission needs.
Get in Touch