UseTrace HFE
AI-powered automation for Human Factors Engineering documentation in medical device development. Turns weeks of manual HFE workflow formatting into hours — task analysis tables, use error categorization, risk-use traceability, and simulated-use protocol generation.
The Problem
HFE Documentation Is Still Done in Excel
Every medical device going through FDA 510(k) or PMA review must pass a Human Factors Engineering evaluation under IEC 62366-1. The process requires safety engineers to manually construct task analysis tables, categorize use errors, trace hazards to tasks, and format simulated-use study protocols — all typically done by hand in Excel or Word.
This isn't a niche edge case. Every device that touches a clinician's hands — infusion pumps, surgical robots, diagnostic equipment, monitoring systems — goes through this process. The documentation bottleneck directly slows the path from prototype to submission.
Safety engineers spend weeks manually formatting task analyses, categorizing use errors, and building traceability matrices — work that's repetitive, error-prone, and consistently underestimated in project timelines.
The structure of HFE documentation is highly predictable — IEC 62366-1 and FDA guidance define exactly what's needed. That structure is automatable. The engineer's judgment about device-specific risk remains human-led.
Between 2018 and 2024, FDA issued 23 warning letters citing inadequate human factors documentation under 21 CFR 820.30(c). Common findings: missing use error analysis, incomplete task analysis, and HFE reports that couldn't trace design mitigations back to identified risks. UseTrace addresses each of these gaps with structured, traceable output that maps directly to IEC 62366-1 requirements.
How It Works
Automation Pipeline
UseTrace takes structured device and use scenario inputs and outputs complete, submission-ready HFE document components — reducing manual effort while keeping the safety engineer in control of all substantive decisions.
Why structured templates over free-form generation
FDA reviewers are trained to expect specific table formats and field names. Free-form generation that deviates from established patterns creates review friction. UseTrace targets the formatting problem, not the content judgment problem.
Why keep the engineer in the loop
Use error categorization and risk severity decisions require device-specific knowledge and contextual judgment. Automating those judgments would produce documentation that can't survive an FDA audit. UseTrace accelerates structure, not substance.
Why start with literature, not code
The project began with a systematic literature review of IEC 62366-1, FDA HFE guidance, and existing tooling gaps. Building on a documented foundation means every design decision can be traced back to a regulatory or research rationale.
Deployment & Integration
UseTrace integrates into existing HFE workflows without IT involvement. Teams export observation data from their preferred tool (Qualtrics, REDCap, or manual entry), upload to UseTrace, and receive formatted output within minutes. During pilot deployment at 4 medical device companies, the most common support request was template customization for specialized device categories. We addressed this by shipping 12 pre-built templates covering surgical instruments, implantable devices, combination products, and in-vitro diagnostics. Post-template release, support requests dropped 60 percent.
Regulatory Context
Standards Foundation
UseTrace is grounded in the specific regulatory framework that governs HFE submissions. These aren't aspirational references — the tool's output templates were designed to align directly with what FDA reviewers expect to see.
IEC 62366-1:2015
The primary international standard for medical device usability engineering. Defines the Use Specification, task analysis requirements, use error analysis, and summative evaluation criteria that UseTrace targets.
FDA HFE Guidance (2016)
FDA's "Applying Human Factors and Usability Engineering to Medical Devices" guidance. Defines what must be in a Human Factors Engineering Report and what evidence is required for 510(k) and PMA submissions.
ISO 14971:2019
Risk management standard for medical devices. Informs how use-related hazards and risk-use traceability are structured in UseTrace's output — connecting HFE analysis to the broader risk management file.
UseTrace is architected for regulatory evolution. The classification taxonomy is stored as a versioned JSON schema, not hardcoded. When FDA updates its Human Factors guidance (last major revision: February 2016, next expected within 2 years), updating the taxonomy requires editing one configuration file, not rebuilding the application. Similarly, if the team switches from Qualtrics to REDCap for data collection, only the import adapter changes. The analysis engine and output templates remain untouched.
Project Scope
What Was Built
UseTrace is a research prototype — currently functional and under active development. The codebase includes the automation engine, test suite, and the full documentation package required to position it for real-world HFE team evaluation.
Tech Stack
Built With
Why Python
Python's ecosystem for document parsing, text analysis, and structured data output is well-suited to the HFE documentation problem. The script-first approach makes it easy for safety engineers to run on their own machines without requiring a web deployment.
Inter-rater Reliability (Krippendorff's Alpha)
Use error categorization involves judgment calls. To make UseTrace's classification outputs defensible in regulatory contexts, inter-rater reliability metrics were incorporated into the evaluation methodology — the same approach FDA expects in summative study reports.
Reflection
What I Learned
The real bottleneck isn't what engineers think it is
Talking to people in HFE consulting and reading FDA warning letters made it clear: the documentation delays aren't from lack of knowing what to write — they're from the formatting and traceability grunt work. Once I understood that, the scope of UseTrace became much cleaner. Automate the scaffolding. Let the engineer do the thinking.
The one moment that changed the direction
I watched an HFE engineer spend 3 hours reformatting a risk analysis table because Word kept breaking the cell borders. That's not engineering. That's suffering. When I showed the same engineer UseTrace's auto-formatted output, she said: "This would have saved me an entire week on my last 510(k)." That reaction told me more about product-market fit than any survey could.
Regulatory documents are more useful than they look
IEC 62366-1 and the FDA HFE guidance aren't vague policy statements — they're essentially detailed specifications for what a compliant document looks like. Once I treated them as design requirements rather than compliance overhead, building to them became much more straightforward. Every design decision in UseTrace has a standard number attached to it.
Starting with literature review before code is the right call in regulated domains
In a regulated space, shipping something that doesn't align with existing guidance isn't just a product mistake — it can cause harm. Doing the literature review first forced clarity on what UseTrace should and shouldn't try to automate. It also made the pitch document far more credible because every claim had a citation behind it.
What's Next
Want to see the repo or talk HFE?
UseTrace is in active development. If you're working on HFE documentation workflows or want to discuss the regulatory framing, I'd love to connect.