February 7, 2011
By Tiffany Hogan, Ph.D - Sr. Research & Product Strategist
It seems that each day we are receiving more signals from the FDA that they are increasingly taking medical device usability testing seriously. Very seriously. The agency is asking for usability testing early and often, and is expecting manufacturers to collect sound data in order to support the claims of safety and efficacy that they are making in their device applications. Having sound protocols for such data collection is intended to help speed regulatory approval of new medical devices. Achieving the level of information and data that the FDA is looking for is not easy. In the past, device manufacturers might simply have had a few of their employees test the prototypes to make sure they were easy to hold, or to see. Today, the FDA is expecting a deep look across the use environment, user characteristics and device characteristics. This means collecting relevant information about where the device will be used, about the physical and cognitive abilities of the expected user, and evidence that the device ergonomics are optimized for the given the circumstances.
As a result of these expectations, manufacturers are expected to weave a great deal of information together in order to present a compelling case demonstrating that it has considered all of the possible use error risks that the device presents to patient safety, and that the manufacturer has adjusted the device design accordingly.
We are increasingly launching human factors engineering projects here at Ximedica that are designed to help our clients navigate these difficult and uncharted waters. We are used to working in this multi-disciplinary fashion and have developed comprehensive tools to ensure that we go deep into all of the required usability areas.
A current project under our roof illustrates our approach. We are working on a hospital-based handheld device, taking it from proof-of-concept right through our current prototype that is nearly ready for design freeze. The first round of work that we completed for our client was a series of visits to hospitals around the country to understand the use environment in as much detail as possible. From this effort we were able to fine tune our clients’ design specifications and we developed several different body concepts. We then set up a concept evaluation, using models/form factors, and put them in front of clinicians in a local medical simulation center. With feedback from the clinicians, we have developed a full working system prototype that is presently undergoing its final formative study in a full usability evaluation. Working with our design assurance team and the engineers, we have set up a simulation in our facility observation room and are asking users to use the system on a patient dummy. Watching the users competently use the system with minimal training assures us that we have created a safe and ergonomically satisfying device.
In order to better understand the expectations of the FDA, we recommend referring to HE-75, “Human Factors Engineering – Design of Medical Devices” best practice guidelines by AANSI/AAMI (American National Standards Institute/Association for the Advancement of Medical Instrumentation), as well as recent guidance documents released by the FDA that are directed towards the development of infusion pumps, but also spell out the overall new usability expectations of the agency.