The device user interfaces with all components of a device with which the user interacts, such as controls and displays (i.e., those parts of the device that users see, touch, and hear). The user interface also includes the device labeling, which includes package labels, any instructions for use in user manuals, package inserts, instructions on the device itself, and any accompanying informational materials.
To gain an understanding of the potential HFE/UE analyses that should be conducted for a particular device, you should consider:
- Identification of the end-users of the device (e.g., patient, family member, physician, nurse, professional caregiver)
- The level of training users will have and/or receive
- User characteristics (e.g., functional capabilities, attitudes and behaviors) that could impact the safe and effective use of the device
- Ways in which users might use the device that could cause harm
Individuals in the intended user populations should be able to use medical devices safely and effectively and without unintentionally making errors that could compromise positive outcomes. With proper application of HFE/UE, the design of a device can be modified to be either less dependent on the abilities of the user or more accommodating of disabilities. For example, people with diabetes often have some degree of retinopathy (a degenerative disease of the retina), which causes impaired eyesight. These users have difficulty reading displays, such as on blood glucose testing meters, especially when the text is small or the visual contrast is low.
Depending on the specific device and its application, device users may be limited to professional caregivers, such as physicians, nurses, nurse practitioners, physical and occupational therapists, social workers, and home care aides. Other user populations may be non-professionals, including patients who operate devices on themselves to provide self-care and family members or friends who serve as lay caregivers to people receiving care in the home, including parents who use or supervise the use of devices for their children. Device user populations may also include the professionals who install and set up the devices and those who maintain, repair, clean and reprocess them.
The ability of a user to operate a medical device depends on his or her personal characteristics, including:
- Physical size, strength, and stamina,
- Physical dexterity, flexibility, and coordination,
- Sensory abilities (i.e., vision, hearing, tactile sensitivity),
- Cognitive abilities, including memory,
- Medical condition for which the device is being used,
- Comorbidities (i.e., multiple conditions, disorders or diseases),
- Literacy and language skills,
- General health status,
- Mental and emotional state,
- Level of education and health literacy relative to the medical condition involved,
- General knowledge of similar types of devices,
- Knowledge of and experience with the particular device,
- Ability to learn and adapt to a new device, and
- Willingness and motivation to use a new device.
You should evaluate and understand essential characteristics of all intended user groups and describe them for the purpose of HFE/UE evaluation and design activities.
- ↑ FDA. Draft Guidance for Industry and Food and Drug Administration Staff - Applying Human Factors and Usability Engineering to Optimize Medical Device Design. June 22, 2011. http://www.fda.gov/MedicalDevices/DeviceRegulationandGuidance/GuidanceDocuments/ucm259748.htm#2