Assessing the usability of medical devices is a critical activity that needs to be undertaken during the design and development phase of a device to guarantee its ease of use, efficacy and safety. It is important to remember that usability is a regulatory requirement, and its verification is included in the General Safety and Performance Requirements reported in Annex I of Regulation EU 2017/745 on medical devices.
Usability verifies how the user interacts with a medical device and is a key component of risk management activities. In fact, when designing a device, it is essential to consider the human factor, and through usability testing it is possible to identify potential hazards, risks and issues related to the use or misuse of the product by the intended user.
Thus, the usability process allows determining:
- The ease with which users interact with the device
- The capability of users to interact with and utilize the device without any errors, risks or significant issues
- The device’s ability to function in the way in which the user expects it to function.
Usability testing of medical devices is a comprehensive process and should be carefully planned and performed under conditions as representative as possible of real-life conditions. Two important reference tools are available for planning a usability test, the ISO 14971 standard related to risk analysis and the IEC 62366 standard specific to usability.
During planning, it will be particularly important to consider:
- The environment: to effectively mitigate risks, it is essential that the test environment is as realistic as possible, in order to evaluate errors that may actually occur in the real world.
- The users: the test should be conducted on all individuals who have a role in using the device, including patients, medical or nursing staff, and subjects responsible for sterilizing or maintaining the device.
In fact, different medical devices may be used in different contexts, resulting in a different type of interaction. A device could be used in a clinical setting only, such as a hospital, by healthcare professionals who are already qualified and trained in managing and using devices. Otherwise, it could be used in a home setting, where it is important to ensure that the use of the device by potentially unqualified users is always safe.
Usability testing will provide key information, including, for example, the accuracy or completeness of the information that users obtain from the packaging, labels, and instructions for use, as well as from the device itself, how users interpret this information, and how they put it into practice to use the device.
The analysis of this data will allow verification or identification of areas for improvement for the medical device in terms of ease and correctness of use, thereby guaranteeing a higher degree of safety and efficacy.