Page 53 - Safety Risk Management for Medical Devices

32 Safety Risk Management for Medical Devices

Tip Start usability engineering right from the start of product development. Though FDA requires
summative studies, they also want a summary of how usability engineering was performed
throughout the design process.

8.1 KEY TERMS

Below, a select group of terms are defined. A clear understanding of these terms is
important in the proper dispositioning of use-errors, and is also beneficial for commu-
nication with team members.

Term Definition
Abnormal Use Conscious, intentional act or unintentional act that is counter
to or violates normal use and is beyond further reasonable
means of user-interface-related risk control by the manufacturer
[14] 3.1
Action Error One of the causes of Use Error. Related to error in performance of
an action, and not primarily due to perception or cognition
deficiencies
Cognition Error One of the causes of Use Error. Related to deficiency in cognition,
and not primarily due to perception deficiencies or the inability
to perform the action
Correct Use Normal Use without Use Error [14] 3.3

Effectiveness Accuracy and completeness with which users achieve specified goals
[14] 3.4
Formative Evaluation User interface evaluation conducted with the intent to explore user
interface design strengths, weaknesses, and unanticipated use
errors [14] 3.7
Also known as Formative Study
Hazard-Related Use Use scenario that could lead to a hazardous situation or harm [14]
Scenario 3.8
Lapse A memory failure. The User had the knowledge but forgets the
knowledge and makes a decision based on incorrect knowledge.
User executes the decision without slips
This term was used in IEC 62366 2007 version, but not used in the
2015 version
Malice Intentional act to do harm to people, property, or the environment
Mistake The User does not have the knowledge and/or User makes a wrong
decision. User executes without slips
This term was used in IEC 62366 2007 version, but not used in the
2015 version
(Continued)