By Ashley Sutherland and Matt Cavanagh, Design Science
Understanding a product’s use environment is as key a building block to designing a usable and useful medical device as understanding the end user. Where a product is used, and who is using it, are inseparable factors, and anticipating how they interplay in device use is a critical and complex task.
Designing for health care professionals is a technical process; clinical needs, workflow impact, and environmental considerations have to be thoroughly understood and addressed. Usability research has to be present from the ground up, from initial contextual inquiry all the way to summative testing. But balancing requirements for home use devices is a different story, so the development approach for these devices needs to consider an entirely different set of factors.
Coming to terms with these differences is a salient trend for developers, as there is a major push toward more over-the-counter (OTC) devices, monitoring solutions, and devices aimed at reducing hospital admission.
From The Hospital To The Home
Consider the variables that designers assess when developing devices:
As medical devices move from the hospital to the home, designers have to take control of an increasingly unpredictable set of variables.
When designing for a class of professionals using devices in professional environments, designers can rely on a certain level of consistency. Environmental conditions and user characteristics might not be identical, but they will bear enough similarities for designers to target and refine their devices.
Physical space, light and noise levels, and temperature and humidity may vary from hospital to hospital and unit to unit, but such considerations are, at the very least, considered. Optimal use conditions are critical in high-stakes clinical environments, so they will generally be an important consideration during construction and renovation. Operating rooms will have their standard conditions, as will endoscopy units, intensive care units, and catheterization labs.
For example, when designing for staff in catheterization labs, manufacturers know what to expect. They can reasonably predict that lights will be dimmed for portions of the procedure when fluoroscopy is in use. They can also reasonably predict that temperatures in the room will be kept cool for the comfort of staff wearing heavy lead protection. They can then turn these reasonable environmental expectations into inputs for appropriate design features.
Importantly, these conditions can be faithfully reproduced in simulated-use testing, resulting in better fits between products and the people that use them. These people, clinical professionals, are experienced users with medical expertise. In general, designers can expect that these users will not be limited by uncorrected impairments of their vision, hearing, or dexterity, nor will they have conditions that may limit their ability to perform or administer a medical product.
As a rule, these users bring a lot to the table when using devices for the first time. They bring years of education and practice. They bring standardized language, transferable knowledge, and a technical, clinical perspective. Such formal training goes a long way in preparing users in clinical environments for safe and effective device use. And when their formal training isn’t enough, they can rely on invaluable human resources, in-person training, and professional networks to help them get their jobs done.
Manufacturers will often send representatives into the field to introduce new devices and supervise initial uses. What’s more, peers and colleagues serve as a living training and troubleshooting resource. In addition to reading instructions for a newly introduced point=of-care testing device, untrained nurses can go to their peers with questions or issues. These professional perspectives can result in personalized training and faster uptake of relevant information.
Essentially, clinical environments often have the ideal, “best-case scenario” use conditions for operation of a medical product. Not only will they have bright lighting, quiet patient rooms, open space (with little to no clutter), and access to ample medical supplies, but they’ll have people and processes in place to support users.
It is safe to assume that designers might find “worst-case scenario” use conditions in home environments. But the benefits of in-home care to recipients cannot be understated; in addition to improved quality of life, convenience, and independence, home care can result in considerable financial savings. As stated in the FDA’s Medical Device Home Use initiative, designing for home environments presents some unique challenges. Environmental unpredictability, limitations in caregiver knowledge, and lack of device usability can cause serious problems for care recipients in home-use environments.
Although clinical environments are exceptionally complex and busy workspaces, they offer a level of consistency and professionalism that designers can rely on. Home environments offer no such consistency, and any human factors professional will tell you that simulating these environments is no easy feat. Conditions are incredibly varied from household to household. Even within households, conditions vary considerably depending on the location within the home and the time of day — from a busy morning in a house with kids to a quiet evening after a long workday. Also, unlike clinical environments, distractions can come from all directions, from pets, kids, and neighbors, or televisions, radios, and laptops.
Keeping devices and supplies clean also can be problematic, as can the desire to reuse supplies to save on costs and trips to the pharmacy. Patients with hemophilia know these costs all too well. A rare condition affecting approximately 20,000 people in the U.S., hemophilia requires around-the-clock care and attention to detail; being mindful of bleeds, both internal and external, can be a fulltime job. But hemophilia isn’t only intensive when it comes to time and attention. It also requires extensive amounts of medical supplies, which need to be kept clean, stored, and organized in patients’ homes. While it may be difficult to design around hard-to-predict use conditions, it is useful to implement mitigations to alleviate the margin of error when designing infusion devices. Simplifying preparation processes and tailoring supplies for at-home infusions can help make treatment more patient-friendly.
Patients with hemophilia and their caregivers tend to receive extensive formal training; but this is more an exception than the rule. Most home users will lack formal training, beyond an hour or two with their doctor or pharmacist. On top of a lack of training, many users also will have physical impairments related to their conditions. Such impairments go hand-in-hand with home-use medical devices. For the 29.1 million people in the US with diabetes – roughly 10 percent of the population according to the Centers for Disease Control and Prevention (CDC) – use of medical devices outside of clinical environments is a part of everyday life. These users need their devices to be highly intuitive, with clear labeling and simple instructions. Most importantly, they need their devices to account for the physical consequences of their condition, like neuropathy of the fingers and diminished vision. Screens with legible writing and large buttons both provide logical solutions to these problems.
Addressing such variability and unpredictability can seem like an impossible task. But what you can do is design for the “worst-case scenario” when approaching medical device design for home environments. By examining the most severe adverse home conditions, designers can find the floor for this user population and make sure that the least capable users can use their devices in even the worst circumstances. Keep in mind that end users are patients and lay caregivers. They generally lack medical knowledge or formal training, relying primarily on instruction from their primary care physicians and pharmacists. They may also have low levels of education and literacy, which can create considerable difficulty when using instructions-for-use and user manuals.
For these reasons, it is imperative that instructional materials for home use devices provide information in a patient-friendly format. Accessible language and generous use of imagery, including illustrations and diagrams, will aid user comprehension and information retention. A good set of instructions will simplify complex topics and provide easily referenceable materials for patients and lay caregivers. Crucially, they can go a long way towards easing the burden on at-home device users. Excessively long, complex patient medication and device instructions — the kind that unfold into a grid of indecipherable text boxes in maddeningly small fonts — can be downright frustrating and unhelpful in times of stress or discomfort.
It should also be considered that, in home use scenarios, the user may have lost or discarded their instructions for use, so leveraging consumer comfort with online materials is a major opportunity. Internet resources can provide scalable, accessible, and inviting support to users who lack the support of peers or colleagues, and while not all patients will be comfortable enough to use these resources, they can make a big difference to those who do. Video tutorials, online FAQs, and even patient forums can provide invaluable support to patients when they need it.
Design considerations for home environments interplay in all medical devices. Whether your company produces everyday products – like syringes and blood glucose meters – or more complex products for specific medical conditions, such as infusions for patients with hemophilia, there are many factors to consider prior to development to ensure a device is safe and effective for home use.
Although contextual inquiry research is an important component of any product’s development, it is absolutely critical when it comes to developing products for the home use market. Seeing how these people integrate medication regimens into their everyday lives provides developers with telling insights that make the difference between devices that should work and devices that do work for their users.
About The Authors
Ashley Sutherland, Analyst - Ashley holds a BS in Psychology and a minor in Anthropology from University of Central Florida. She also holds an MS in Human Factors and Systems from Embry Riddle Aeronautical University. Ashley contributes to all aspects of usability studies, including protocol creation, study moderation, data analysis, and report writing.
Matthew Cavanagh, Analyst - Matt received a BA from the University of Pennsylvania, where he studied International Relations and Anthropology. Matt specializes in ethnographic research, with experience managing data analysis, research synthesis, and deliverable creation.