By Charles L. Mauro, Mauro Usability Science
This is the first of a two-part series taking a hard look at current human factors engineering (HFE) testing methods and looking at new advanced testing methods that HFE teams can utilize to improve the HFE performance of medical devices. Part two of this article will be published June 14, 2018.
Human factors engineering and related usability testing is a critical aspect of FDA medical device guidance that has led to improvements in HFE performance for many medical devices. However, the methodologies employed by those conducting HFE optimization studies and usability testing — as discussed in both HE75 and the FDA’s HFE guidance — are based on surprisingly out-dated research methods, developed more than 100 years ago by Fredrick Taylor and others.
Current HFE research employs simple task-based observation of patient behaviors, “think-aloud” descriptive processes, and debrief interviews. The last major advance in traditional HFE testing was the addition of video recording for post-study review introduced 30 years ago. Even though these traditional methods are well understood to be highly subjective, error prone, and subject to all manner of self-reporting biases, they continue to be the methods of choice for the vast majority of HFE device usability studies. Even current FDA guidance and HE75 proffer such methods as the primary means of assessing devices’ HFE performance.
It is important to note that these traditional observational methods have value when assessing HFE performance, but there is now a pressing need to supplement subjective, observation-based testing methods with more objective, neuroscience-based data capture systems. The combination of testing methods will produce much more usable and productive medical devices, as well as improved clinical outcomes and reduce FDA review and approval processes.
On a higher level, HFE testing as a professional discipline has not taken advantage of a wide range of advanced and well-understood physiological, biomechanical, cognitive, and emotional sensing and testing modalities. For more than a decade, these new systems have provided medical research professionals and associated engineering teams with a vast and powerful new set of data focused on understanding human behaviour in a wide range of domains.
Application areas for these new testing systems include neuro-marketing, cognitive neuroscience research, applied medical research, aerospace, aviation, transportation, athletics, education, consumer products and a wide range of military applications. These commercial domains have embraced advanced neuroscience-based testing based on an understanding that better overall system performance demanded much deeper understanding of human response to new technology.
New Methods For New Device Design Problems
Traditional HFE testing methods may have been appropriate for simple, traditional medical devices, but the incoming generation of devices presents to patients and HCPs more status indications, more complex errors states, more complex interaction behaviours, less familiar device form factors, new IFU formats, more complex drug delivery schedules, and new, larger-molecule biologics, as well as a new generation of wearable devices and associated smartphone apps.
The time has arrived to supplement traditional observational methods with scientifically-valid HFE testing methodologies that support the creation of medical devices (and related medical technology) that are objectively focused on meeting the cognitive, emotional, psychological, and physiological needs and limitations of patient populations who differ from the healthy population in important ways that measurably impact clinical outcomes.
Neuroscience-based data-capture systems can produce unified data streams that provide device engineering teams with unprecedented access to valid HFE research data, which can be utilized to objectively optimize medical device HFE performance, as well as all manner of IFU and package design solutions.
This approach also will aid the FDA in defining new HFE performance requirements and related testing methods, as well as shorten the time required to conduct HFE reviews and certify compliance. It is only a matter of time before the FDA begins moving toward neuroscience-based HFE performance guidance that is based on objective and engineering-focused HFE criteria derived from the application of advanced HFE research methods. Other major governmental agencies have defined product performance guidance in science-based terms for decades. Further, the opportunity to base patent claims on objective HFE performance improvements is a major benefit for those creating new medical device solutions.
New sensing modalities now make it possible to capture data on a wide range of physical device states — including device location, angle of injection, depth of injection, interaction 3D profile, patient hand tremor levels, and interaction forces — previously impossible to measure accurately and at reasonable cost. Neuroscience-based data capture also can measure cognitive and emotional responses to medical devices, including cognitive workload, emotional response, and learning decay.
These new methods can be applied to simple, single action auto-injectors or highly complex augmented reality robotic surgical systems. Finally, in addition to creating new devices, these methods can be used to optimize existing devices’ hardware, software, and apps.
New Device And Patient HFE Testing Modalities And Technologies
These new data capture methods already have been successfully integrated and utilized to produce powerful insights related to medical devices’ HFE performance, instructions for use, and packaging. However, it is important to note that these new systems do not totally replace traditional observational research; they provide a large measure of objective data that verifies, builds upon, and augments our understanding of medical device HFE performance.
However, creating advanced HFE testing systems is not without its challenges. Part two of this series, slated for publication on June 14, 2018, will discuss the challenges and benefits of employing new advanced neuroscience-based testing methods in the creation of improved medical devices and related procedures.
About The Author
Charles L. Mauro, CHFP is Founder and President of MAURO Usability Science, a New York-based consulting firm founded in 1975 specializing in advanced human factors engineering research and the optimization for complex medical devices and related technology. He is Chairman of the Design Protection Section for the Industrial Designers Society of America and is the IDSA liaison to the US Patent and Trademark Office. He has lectured on product design and human factors engineering research at MIT, Stanford University, UPenn, and many other leading human factors research and engineering programs. Over his 47-year career Mr. Mauro has managed over 4,000 HFE research and development projects.
Mr. Mauro holds a BS with distinction in Industrial Design from The Los Angeles Art Center College of Design and a Master’s Degree in Ergonomics and Biomechanics from New York University. At NYU he was an appointed NIOSH Research Fellow at the RUSK Institute of Rehabilitation Medicine. His experience with complex medical technology spans more 47 years.
Reviewers: The author would like to thank the following reviewers. The content of this article is based solely on the opinions of MAURO Usability Science and, specifically, the author. It may not reflect opinions of the reviewers or their organizations.