Nearly 90% of FDA 510(k) submissions receive reviewer comments related to human factors engineering. Human factors engineering (HFE), which is synonymous with “usability engineering,” calls for applying knowledge about users’ behavior, expectations, abilities and limitations to design with safety, effectiveness, usability and satisfaction in mind. With the majority of FDA submissions receiving HFE-related questions and pushback, FDA is clearly upholding its written expectations.
Andrea Dwyer, Associate Research Director of Human Factors Research & Design at Emergo by UL, spoke at RAPS Convergence 2020. In her presentation, Dwyer emphasized what a good human factors process looks like, as well as best practices for successful FDA submission.
While these four steps and practices are likely not new to you, they serve as a refresher for what FDA is closely considering with your submission.
1. Apply Human Factors Engineering Early and Often
“HF [Human factors] is an iterative process, not just a checkmark,” Dwyer said.
Engineers need to consider human factors throughout the entire design process. Further, some steps will have to be repeated over the course of your devices’ development. You simply cannot consider human factors just once and then move forward.
2. Define Intended Users, Use Environments and Use Errors
“You really want to understand who your users are and what needs they may have,” Dwyer said.
It’s also important to understand the environment in which someone will use the product, whether that’s a home or a complex clinical environment, to adequately design your device. She says the best way to do this is by watching people use the product in the environment in which your product will be used.
“This is tougher during COVID-19, but there are ways to remotely observe and interview, or conduct web surveys or desktop research like literature review and leveraging your internal documentation,” she said. “Unfortunately, FDA has not made exceptions in light of the pandemic.”
3. Mitigate Use-Related Risks
Your goal is to design a safe device that will ward off risks. This involves conducting a use-related risk analysis, breaking down use steps and analyzing the associated risk and possible harm of each. User-related risk analysis can take many forms such as in a spreadsheet with rows and columns corresponding to the use steps and possible errors, and then rating the associated potential harm.
Dwyer recommended developing user-interface requirements based on your research, and then refining the design based on what you learn. These can relate to various aspects such as alarms, touchscreens and cleaning.
“User needs translate directly into user-interface requirements, which lay the foundation for good user-interface design,” she said. “Verify that the final design satisfies the user-interface requirements. They don’t have to be super complicated. It’s better if they are clear and simple enough to feel confident that you’ve effectively designed to the requirement.”
Conducting formal evaluations is key to human factors engineering, Dwyer stressed.
“This can be fun because you get to understand if people are able to work with the design and note any system strengths or shortcomings,” she said. “You can do this by hands-on testing or expert reviews from HFE specialists.”
4. Validate Your Design and Document According to FDA’s Format
Usability testing can help prove that your risk control measures are working.
“HFE validation tests are essential to making sure that the product is safe and effective, therefore meeting FDA expectations,” Dwyer said. “At this point, it’s no longer about continuing to improve the product, but evaluating the final design and confirming that users can complete critical tasks without leading to harm.”
After validation tests are complete, it’s time for FDA submission. Dwyer recommends sticking to the format that FDA outlines in its Appendix A HFE/UE report.
“FDA’s guidance is very clear, outlining eight chapters where you should describe the HFE work you did from beginning to end,” she said. “It’s really well done and there isn’t a reason to deviate from the outline they provide. Use it to tell a great story about your HFE work.”
Dwyer reminds that the main goal is to make a claim to FDA and back it up with your HFE work. FDA actually lists this ultimate claim: The [device] has been found to be safe and effective for the intended users, uses and environments.
“If you don’t feel like you can say this, make sure to attend to that before submitting,” she said. “FDA is particular about their expectations of HFE and what is considered safe and effective.”
Human Factors Success Requires a Plan and Communication
Dwyer also recommended the following keys to success when applying HFE:
• Have a company HFE project plan and make it required along the way
• Apply HFE to labeling and packaging, as well as hardware and software
• Develop task-oriented solutions that match the user’s expected workflows
• Communicate with FDA to receive feedback on HFE plans and protocols prior to proceeding
“The last point is the No. 1 thing you can do to ensure your success,” she said. “FDA is very open about its willingness to help and is eager to provide feedback, which is helpful as it releases new guidance every year.”
Kathie Zipp is an ORTHOWORLD Contributor.