Applying Human Factors Engineering : Naturally Safe Software–User Interfaces

Stimulated by regulations and standards as well as commercial imperatives, medical device manufacturers are striving to make medical devices safer by decreasing the potential for harmful use errors. Accordingly, manufacturers are observing and interviewing intended users about their interactions with devices en route to developing user interface requirements; applying human factors engineering (HFE) principles when designing user interfaces; and conducting formative and summative usability tests to improve and validate their devices’ interactive quality. This has represented significant work for manufacturers, particularly the majority who started with little HFE knowledge and experience. Today, the “awakening” to HFE in medical device development is essentially over—an established manufacturer who is just now discovering HFE has been out of touch. After all, the U.S. Food and Drug Administration (FDA) and AAMI conducted their first joint conference on HFE in 1995 when they previewed HFE expectations related to recent changes in quality system regulation (QSR). So, it has been 17 years since HFE entered the medical industry’s zeitgeist. HFE specialists working in the medical industry used to focus on making devices more usable (i.e., user friendly). Since the QSR change, use safety has become the primary focus, resulting in user interfaces that are less vulnerable to harmful use errors. It is rather obvious how HFE affects the safety of some medical devices. In the design of a surgical instrument, for example, HFE’s aim would be to reduce the chance of cutting anything other than the intended target. This goal could be accomplished by including a blade guard and a mechanical interlock that requires more than one deliberate action to enable cutting.