Debbie McConnell, Human Factors Lead, Battelle 06.08.16
By now, medical device developers are well-acquainted with FDA requirements for human factors and usability testing. But if you’re only doing the required pre-market regulatory submission testing, you’re missing out on the significant benefits that human centric design (HCD) can deliver to your sales numbers and your bottom line.
FDA requirements are focused on device safety and effectiveness. A truly human-centric process goes beyond safety and efficacy and looks at how the device will be received by its intended users and how it fits into their lifestyle or workflow.
At its heart, HCD is about ensuring that the devices and apps we develop for patients and providers work for the humans that must operate them, in the environments in which they will be used. By considering human factors from the very beginning of the design process, medical device developers can avoid costly redesigns prior to market release. They will also uncover unexpected insights that can significantly increase market acceptance and ultimately sales. Users can’t always clearly articulate what they want or need in a device and often don’t know what they want or need until they see it. With HCD, we can find and satisfy these hidden needs and develop products that are not only safe but also highly desired by patients and providers.
In fact, incorporating HCD principles throughout the development process can actually save money in the long run. For maximum benefits, HCD should not be a last-minute add-on to the design process but a design philosophy that infuses the entire development process from concept development to market release. By starting with a human-centered approach from initial concept, developers can reduce the risk of costly redesigns and increase the chances of market success.
To illustrate this concept, let’s take a look at two companies we have worked with recently; we will call them Company X and Company Y. Both are developing new medical technology that will provide significant value to their users and to the market. Company X has spent several years conducting market research activities and developing a next-generation product. As the project moved through their internal development processes, it proceeded into the stage that required formative usability studies with intended users. Instead of conducting usability studies that would yield objective design inputs, the marketing team held focus group sessions. New features were added based on the subjective focus group feedback, and the company was certain that these features would be strong selling points in the marketplace. However, when we conducted the first actual usability study late in the product design phase, several issues were uncovered almost immediately. Unfortunately, addressing those issues required significant redesign of the product, forcing Company X to evaluate the cost of redesign vs. the cost of shutting the project down. Sadly, the cost of redesign, combined with lost revenue resulting from a delayed launch, proved to be too high and the product was ultimately shelved.
In contrast, Company Y built a robust HCD effort into their three-year development plan, enabling our team to start gathering relevant user data from the very beginning and allowing the data to inform design decisions. For example, rather than designing the instructions for use (IFU) in a vacuum and then testing with users late in validation, we were able to run a series of early human factors activities designed to elicit what specific elements of the device were important to safe and effective use. These insights were combined with several co-development activities, allowing the users to create their “preferred” instructions. These user-generated IFUs were refined and formally tested and the resulting data proved that users could understand and safely use the device as intended. What Company Y understood was the fundamental difference between market research and HCD. Market research focuses on user preference, while HCD focuses on both preference (what users want and need) and performance (what actions users are capable and not capable of performing).
A comprehensive HCD approach uses a “learn early, learn often” philosophy in order to uncover potential issues early in the development process when they are cheaper and easier to fix. HCD should not be thought of as an “add on” expense. It is an investment that when done right, will more than pay for itself over time.
But what does this actually look like in practice? At each stage of the design process, there are specific activities that developers can engage in to ensure that the final product will be safe, effective, and well-received by users.
Contextual research is done at the beginning of the development cycle, before design work even begins. Contextual research is designed to help identify unmet intended user needs and determine what device features would best meet those needs. It may involve user surveys, focus groups, and in-depth observational studies. The challenge with contextual research is that intended users are not always able to put their needs and desires into words. They may not fully understand their needs themselves or be able to imagine what kind of device or feature would meet their needs. Users “don’t know what they don’t know” and can’t express their reaction to devices they have not yet seen. For this reason, observational studies, in which trained HCD researchers watch intended users interact with their current devices or perform related activities in their natural environment, may be more valuable than user surveys. Unlike market research activities, experienced HCD researchers are able to take these (often ambiguous) expressed and unexpressed needs and translate them into technical specs and device requirements, elements which are critical to ensure that these deep insights are able to be leveraged by the engineering development teams. Contextual research is especially helpful at the beginning stages of developing a new medical product or before engaging in a major redesign of an existing product.
At the concept development stage, HCD principals can make product design more efficient by evaluating the evolving design with intended users. Rapid digital prototyping and 3D printing technologies have made it easier and cheaper to produce and evaluate multiple versions of a device or component. Heuristic evaluations done by human factors experts are another early and relatively inexpensive technique for improving the product design.
Human factors usability studies occur at all stages of design but increase in intensity and focus in the later stages of product development. The final human factors study, called the summative usability study, evaluates production equivalent devices. This summative study is the pre-market regulatory submission safety and efficacy testing for FDA approval. Usability study activities may include heuristic evaluation, ergonomic measurement, and human performance testing. At its simplest, usability studies mean actually getting the product into the hands of intended users and watching to see what happens, refining the product design, and running the study again. Usability studies can uncover unexpected safety or efficacy issues that occur when users actually interact with the product. Corrections made at this stage range from refining the device design to changing the way user instructions are presented. While usability studies are a required step prior to final market release, developers can actually start this process as soon as a working prototype is available.
The HCD team at Battelle works with medical device developers at every stage of the design process. In a recent project focused on surgical site preparation, we started with contextual research to gain insight into how their current product performed in the field. Hospital observational studies identified two design issues that impacted patient safety. First, the preparation of the existing product sometimes resulted in a broken device, which was undetectable to the user until it caused visible harm to the patient. Second, the time between application and use was critical. As a result of our research, we were able to overlay the unmet user needs with human factors anthropometric data. Combining these vantage points resulted in several “opportunity areas” that not only improved the user experience, but mitigated the causes of previous use errors.
Done right, HCD is much more valuable than just a required pre-market regulatory submission study. It’s a philosophy of design that infuses every stage of the design process. By considering the human as part of the system, medical device designers can ensure that their devices will be not only safe, but also successful.