A Chronically Underutilized Role in New Medical Device Development
Utilizing this role to its fullest could minimize project risk and speed your product to market.
A Chronically Underutilized Role in New Medical Device Development
Very few medtech companies are using human factors (HF) professionals in the way that makes the most sense. At Delve, we believe that instead of being brought in to consult at the end of a project, human factors should be involved from the beginning and throughout a project.
In this article, I'll explain how to fully leverage human factors expertise to reduce risk in medtech development, what happens when HF is used to its fullest, and, if you can’t use it like we suggest, how to still reap some of the benefits it provides.
How to Underutilize a Human Factors Expert
Treat them like a movie critic.
My friend and former colleague Craig Conner once explained it this way. A movie critic watches a movie, critiques it, and offers some opinions on how the movie might have been better. The critic wasn’t involved in making the movie. They’re just assessing someone else’s work.
Similarly, design teams sometimes engage human factors only in the late stages of a project. HF runs a summative study to assess the design at that point in time—a design into which HF probably didn’t have much input. HF identifies use errors and evaluates safety, the critical issues that interest the FDA. They write some documentation and make some recommendations for risk reduction.
This is fine as far as it goes. Bringing in HF to design, run, and report the results of a study—regardless of the stage of the design—is useful.
But what's to say the request occurred at the most appropriate time, or with the appropriate stimuli? What if an earlier study could have refined or eliminated features or functionality? Depending on the stage of the design when the study is run, it may be too late to influence the design without costly and time-consuming rework. We have seen whole products get scrapped because the cost of backtracking wasn't something the company was willing to support.
A movie might survive a bad review. A bad summative can cost millions of dollars—or kill a product entirely.
How to Fully Utilize a Human Factors Expert
Treat them like a movie director.
Instead of being brought in to consult at the end of the project, human factors should be involved from the beginning and throughout the project, “directing” development with key input at every stage, and not just through user studies.
Human factors practitioners who have the background, experience, and proficiency to collaborate with a design team and influence a design as it emerges can have a dramatic effect on a final project’s cost and timeline, as well as the final product’s usability and market acceptance.
Human factors expertise is invaluable when utilized to its full potential. Integrate it into the front-end of the product development process.
Human Factors should be like a movie director, not a movie critic. Instead of being brought in to consult at the end, HF should be involved throughout a project, “directing” development at every stage.
7 Benefits of Integrating Human Factors into Your Design Team
We’ve experienced at least seven ways integrated HF can benefit medical device projects. (But if integration isn’t realistic for your situation, we’re also going to share guidance for filling the gap.)
1. Integrated HF minimizes overall project risk.
One of the most expensive things that can happen in a project is to get to the end of development and discover that you didn’t design what you set out to design or you designed something that doesn’t pass muster with the FDA with regard to human factors.
This is a huge setback even for established medtech companies. For smaller startups, it’s a setback that can prove impossible to surmount. We have seen many projects reach this point then fail to reach completion because it would take too long and be too expensive to go back and address issues uncovered at this late stage.
At the highest level, integrating human factors into your project from the beginning minimizes the chances of any HF-related surprises at the end. It also maximizes the chances the product will be designed with the end user and use environment in mind, which can be an important market differentiator between like products.
Instead of waiting until the late stage of development to uncover potentially insurmountable design problems, you test increasingly realistic iterations of a concept. You identify and address any problems along the way, at points in the development process when they are easier and less expensive to fix. By the time you conduct the final summative study, you already have a clear idea how participants will perform.
Integrated human factors minimizes the chances of HF-related surprises at the end.
2. Integrated HF ensures end users' needs are represented throughout development.
When you interview a clinician about a medical device they have been using, they may be able to tell you quite a bit about the device itself, but they can’t tell you the things that they don’t even realize they do. They can’t tell you they struggle with something but don’t realize it. They can’t tell you they use workarounds that have become so routine they’ve forgotten they use them.
This is why integrating human factors should begin with contextual inquiry, long before design starts. A trained HF practitioner, observing the user in the device’s actual use environment, can pick up on important details of which the user is unaware. Then they can draw out the back stories during user interviews, often uncovering important insights. This early immersion in the life and world of the user equips the human factors practitioner with a deep, nuanced understanding of the user environment and what the user wants and needs.
HF can then leverage this foundational empathy and knowledge to represent the end user throughout the entire design process:
- Findings from contextual inquiry enables HF to help shape what the design should be, including defining testable and traceable user needs and use-related requirements. This sets the team on the path to designing the right product.
- Integrated into the design team, at any point in the development process, HF helps guide decision-making from the viewpoint of the end user. This maximizes the chance that emerging concepts will meet the needs of end users and fit into the users’ desired workflow.
Nothing can fully replace direct user feedback, so eventually, the design team will bring users back into the development process. Until then, HF serves as the voice of the user within the design team itself.
With knowledge gained at the early stage, HF can represent the user within the design team and set you on the path to designing the right product.
3. Integrated HF minimizes the number of user studies required.
Too much user input is rarely a problem. At the same time, few development projects have the time and budget to run unlimited user studies to explore and refine design concepts.
In our experience, at this stage, design teams without integrated HF are prone to either running formative studies unnecessarily or waiting too long to run a formative study. In the latter case, they end up progressing too far down a design path, only to have to backtrack significantly when user feedback tells them they are on the wrong track or usability problems become obvious once a real user interacts with the design.
Having an integrated HF practitioner on your design team as concepts mature allows you to know when to shift from being internally focused to soliciting feedback from end users, so you can avoid both problems.
- You reduce the number of user studies needed to choose the right features and functionality for your product. Integrated HF can help guide the team to time- and cost-efficient alternatives to user studies, when appropriate. For example, the design team may have questions early in the process that don’t necessitate a full 6-8-person study (assuming one user group). Having a clinical advisory board on call may be the right solution. The design team could ask their questions with a few hours’ notice instead of the two or three weeks it takes to recruit and run a user study. In a different scenario, attending a conference and talking with attendees could be the best way to get the answers you need. The goal is not simply to reduce the number of user studies required, but to make sure you are obtaining feedback from the right people at the appropriate time and place—and there are creative ways to do that.
- You reduce the number of user studies needed to minimize the chances of developing the wrong design concept. When human factors is involved in contextual inquiry early in development, they become content experts who can often predict which concepts or aspects of concepts will not work well for specific reasons. Yes, sometimes, we absolutely need to put things in front of users, but with HF embedded in the design team, representing the user’s point of view, many concepts can be eliminated sooner and without spending the time and money to conduct an actual user study.
At Delve, we love user studies. There is definitely a time and place for them, and you should run as many as you need to be comfortable with your design—but no more.
With HF on the team representing the user’s point of view, many concepts can be eliminated sooner, without spending time and money on a user study.
4. Integrated HF allows you to create appropriate stimuli for user studies.
Creating overly realistic or complicated stimuli for user studies is a common development mistake. Take this scenario: A design team is developing a new medical device with both physical and digital interfaces. Without integrated HF to guide them, they decide to wait until they have an alpha prototype to test interfaces for the first time because “that’s the first time the various device interfaces will work in a holistic manner.”
What they would have known, if human factors had been integrated into the design team, is that you don’t always need a fully developed product to get the feedback you need. When considering high-level touchpoints of an emerging product, like general form and aspect ratio, the stimuli you test doesn’t need to look anything like the end product. If anything, you want to avoid building in too much realism, so test participants will focus on the aspects of the design that concern you.
Remember, you only need stimuli of high enough fidelity to get valid answers to your question. Building models is expensive. Overdeveloped testing stimuli don’t just potentially compromise your test results—they are also a waste of time and money.
In our sample scenario, a design team with integrated HF would lean on human factors expertise to ensure that the physical and/or digital stimuli for the study was appropriately limited to whatever features or functionality needs testing at that stage. HF would help design stimuli to get the usability-related answers needed while also making sure test responses are not biased by aspects of the stimuli unrelated to the aspects of the design under review.
For instance, early in the design process, cleverly designed user experience (UX) models, possibly incorporating non-functional buttons and an embedded digital prototype, would be an appropriate solution, and could be cheaply and quickly made.
Creating cheap yet effective UX models reduces project risk overall by testing interactions and feature sets well before all those features interact with each other in a holistic manner. This reduces project risk by enabling the team to either validate the current design direction or redirect it, much earlier in the project timeline.
Integrated HF helps you create the proper stimuli for user studies—just high enough fidelity to get valid answers, no more.
Project Example: Dexcom G6
Any member of the general population can develop diabetes and become insulin dependent.
So, the central challenge Delve faced in designing the Dexcom G6 Continuous Glucose Management (CGM) System was to take the mechanical guts needed to make the Dexcom CGM applicator function and encase it in a new form so intuitive that any user could operate it easily and correctly—regardless of age or education level, without special training or instructions, and regardless of their environment.
Having observed users struggle with earlier devices, Delve's integrated HF practitioners knew the new Dexcom applicator would need to be stable on the skin and have many different grip orientations. They knew the needle and sensor would need to enter the skin at a certain angle. Insights like these enabled HF to contribute to design requirements that would set the team on the path to the right design. Collaborating with the design team from the beginning, HF made sure the entire team understood the problem the same way and had the same starting point of things we knew had to be solved.
As the design matured, HF guided the creation of appropriate models for user studies. In alignment with our principle that user study stimuli only need to be of high enough fidelity to get valid answers, our first models were carved out of foam. They were realistically sized. The button was spring loaded to the proper force. They did leave a patch on the skin. But they had no actual internals.
This is a good example of creating simplified user study stimuli that are not just faster and less expensive to make, but also focus user attention on the aspects of the design that are being assessed at a given time. They enabled us to quickly gather user feedback on which designs worked best and why, so the design team could iterate as efficiently as possible.
Learn more about Delve’s work on the Dexcom G6.
5. Integrated HF enables tracking and minimizing the number of critical use errors.
The final and toughest hurdle you must cross before you can launch your new medical device is earning FDA approval. To achieve this, you need to demonstrate that you have minimized the likelihood of critical use errors that could result in serious harm to the patient or user.
Integrated HF significantly eases the path toward this goal.
Simply put, the most effective way to minimize the number of user errors in your final summative study is to design them out. With HF integrated into your design team, human factors findings from early contextual inquiry can guide your entire development process, maximizing the chances you can mitigate potential critical use errors by design. Mitigation by design means those potential use errors simply will not exist in your final design.
There will be many instances throughout development when human factors expertise, integrated into your design team, will be able to help you eliminate certain user errors entirely. Here’s one concrete example. Early in development, you realize that using an expired drug is an error you need to mitigate. So, you design a drug label that includes a QR code with an embedded expiration date. You also design the device that delivers the drug to include a bar code reader that will not accept expired drug. Result: It is now impossible for users to make this particular error.
As you move through development and run increasingly realistic user studies, integrated HF helps you identify and mitigate more potential user errors. They also track and thoroughly document these risk management efforts throughout the development process.
Of course, it is very difficult to design out all potential user errors. But addressing potential sources of critical use errors early enhances the usability, safety, and effectiveness of your device. Then, if your final summative study shows that a potential error remains, the human factors documentation that you have created and curated throughout will tell the full story of how you arrived at the final design and all the things you tried along the way to minimize the chances of that particular error. This puts you in a strong position to demonstrate to the FDA that you have taken all reasonable steps to reduce errors, facilitating regulatory approval.
The most effective way to minimize the number of user errors in your final summative study is to design them out. Integrated HF enables this.
6. Integrated HF allows for real-time, iterative output.
If your design team has a “movie critic” type of HF partner, it usually takes six to eight weeks from the time you decide you need to run a study before you get results. This time frame includes recruiting, designing the study, running the study, analyzing the results, then reporting on the results. It's a long time to wait to learn how your emerging designs are faring and what you might need to do to make them better.
Integrating HF into your design team promotes a more collaborative approach, in which every member of the design team is present during each HF study. This way, everyone sees first-hand what users do and what they struggle with. If multiple study participants struggle with something, the design team can be thinking in real time, during the actual study, about what might be changed to make that particular part of the design better.
Also, the entire team should have a debriefing session after each study participant, to discuss what you have seen and what you think it might mean. You can immediately consider design changes that might be needed.
Quite often, after the first few participants, you will have a pretty good idea what you need to do. Certainly, by the last participant, your team will have seen trends emerge, and what you need to do next will be abundantly clear. A full human factors report will follow, providing supporting information, but even before it arrives, you should be able to get a top line readout.
Instead of waiting eight weeks to know how your emerging designs are faring, your design team can directly observe study participants and consider design iterations in real time.
7. Integrated HF enables you to identify and address critical usability problems early.
As the design becomes more defined and more features are added, having HF integrated into the design team means you will be able to tackle potential user errors as soon as they can be identified in the evolving design.
Later in the development process, when the product is being engineered and alpha or beta prototypes are available, integrated HF team members focus on testing critical tasks that could not be adequately tested earlier.
But even at this late stage, the earlier a usability problem can be identified, the easier it is to fix. Integrated HF enables your team to solve usability problems when it costs less time and money to address them.
Integrated HF enables you to tackle design problems as soon as they can be identified—i.e., when it costs less time and money to address them.
Project Example: ProNova S360
The proton therapy system that Delve designed with ProNova is one of the biggest, most complex, and expensive medical devices in the world. It has a very large number of user touchpoints. During development, this translated into a staggering number of potential use errors to consider and address.
Delve’s integrated HF practitioners helped the design team understand the complexity of the problem from the outset and put different aspects of the interface into proper perspective. Human factors guided design with an understanding of what users were physically doing at different stages of this hour-long therapy, what information was critical for them to have at each stage, and where and how the information should be provided.
We needed to assess our emerging concepts in as realistic a use environment as possible, but only three or four very proton therapy centers existed in the country at the time—all far too busy to host our usability studies. So, we built our own, two-story-tall model of a proton therapy room. Then, we built the various relevant user interaction touchpoints in higher fidelity. We used a combination of 3D printed, clickable prototypes and projections, and paper prototypes to assess specific user interaction touchpoints. Working with proton therapy technicians to test successive iterations, we were able to ensure that we were on the right track with the emerging design.
The final ProNova S360 encompasses two rooms and a 360-degree, rotating proton therapy “gun” It’s a good example of how integrated HF reduces project risk. On such a large and complex project, it would have been impossible to shift design direction late in development to address usability problems uncovered at that stage.
Alternative Approaches to Reaping the Benefits of Human Factors Integration
While the ideal scenario involves fully integrating HF expertise into the design team from the outset, restructuring product development processes can be daunting for many companies.
If your company is stuck in its ways, here are approaches you can use to gain some of the benefits of integrated HF—without a complete overhaul of existing practices.
- To Minimize Overall Project Risk
Even without integrated HF, companies can mitigate risks by prioritizing early user feedback through methods like advisory boards or small-scale formatives. Encourage interdisciplinary collaboration by regularly involving HF professionals in project meetings, allowing them to provide insights and flag potential usability issues.
- To Ensure End Users' Needs are Represented Throughout Development
While direct observation may be limited, companies can still gather valuable user insights through surveys, interviews, and observational studies conducted by external HF consultants or research firms. Ensure that user feedback is systematically incorporated into design decisions by establishing communication channels between design teams and end users.
- To Minimize the Number of User Studies Required
To minimize the number of user studies, leverage existing data sources such as literature reviews, competitor analyses, or industry reports to inform early design iterations. Focus on targeted user studies for critical decision points rather than conducting exhaustive testing at every stage.
- To Create Appropriate Stimuli for User Studies
Even without integrated HF, companies can optimize testing stimuli by collaborating with HF specialists on a project basis. Provide clear direction to external consultants regarding what answers the study is trying to find. For example, “Is this the right feature set?” or “How do users respond to a specific critical task? - To Identify and Address Critical Use Errors Early
Utilize risk management techniques such as Use Failure Modes and Effects Analysis (uFMEA) to proactively identify potential use errors and prioritize risk mitigation strategies. Conduct regular usability assessments throughout the development lifecycle, incorporating feedback from clinical advisors or domain experts. - To Enable Real-Time, Iterative Output
While real-time involvement may be challenging, companies can still promote iterative design processes by fostering a culture of openness to feedback and continuous improvement. Schedule regular design review sessions to discuss interim findings and adjust development plans accordingly. - To Identify and Address Critical Usability Problems Early
Encourage early user involvement by establishing advisory panels or user forums to gather feedback on preliminary designs. Implement agile development methodologies to facilitate rapid prototyping and iteration cycles, allowing for timely adjustments based on user input. - To Identify Areas for Improvement and Inform Design Decisions
Engage external HF consultants to perform HF gap analysis and heuristic analysis on your product designs. Assessing the current design against established HF principles and standards will help identify discrepancies and areas for improvement. Similarly, heuristic analysis can identify potential usability problems and provide actionable recommendations for improving user experience and reducing risks.
Aim to fully integrate human factors into your design team. Until then, embrace flexibility, collaboration, and a commitment to user-centricity to enhance the usability, safety, and effectiveness of your medical devices.
Fully integrating human factors into your design team is a strategy that can spell the difference between success and failure in the high-risk endeavour of medical device development. This approach ensures that you develop the right product that meets users where they are. It reduces overall project risk by reducing costs and accelerating time to market. It proactively addresses usability challenges, minimizes use errors, and ultimately delivers a medical device that meets regulatory requirements for safety and effectiveness.
Learn more about our Human Factors Product Development Engineering Services.