Human Factors and Usability in Healthcare Technology
This domain covers how device design and the care environment produce use-related hazards, and how those hazards get evaluated under IEC 62366-1.
Core concepts
A use error is an action or failure to act by the user that leads to a different result than intended; it is not negligence. The usability engineering process defines intended users, use environments and user interface characteristics, identifies hazard-related use scenarios, then runs formative evaluation iteratively during design and summative evaluation to validate that critical tasks can be performed safely by representative users. AAMI HE75 is the standard human factors design reference; IEC 60601-1-8 governs alarm systems.
Alarms and workload
Alarm fatigue comes from excessive default limits, indistinguishable sounds and delayed response. Controls include prioritized alarm signals, adjustable defaults, delays, centralized alarm management and a documented alarm management program.
Environment
Lighting, noise, glove use, reach, interruptions and handoffs all change error rates. Anthropometric design targets the 5th percentile female to the 95th percentile male.
Worked example
A syringe pump summative test has fifteen representative nurses perform eight critical tasks. Two participants silence a high-priority occlusion alarm believing it is a battery alert, because both icons are amber and the tones are similar. That is a use-related hazard requiring interface redesign, such as distinct color, text and sound, rather than a training bulletin.
Traps
- Confusing formative evaluation with summative validation.
- Testing with engineers or colleagues instead of representative users.
- Treating every use error as a training deficiency, leaving the design unchanged.
- Ignoring the environment where the device will actually be used.