Reasonably foreseeable misuse in the context of ISO 14971 is more than use-error.

Note: this article is a summary of the original article published on the Let's Talk Risk! newsletter. Read the full article here.

Summary

When it comes to managing risks associated with reasonably foreseeable misuse of a medical device, a common industry practice is to focus on use-error(s) and apply the principles of usability engineering according to IEC 62366-1. However, the scope of reasonably foreseeable misuse in ISO 14971:2019 is more than use-errors that can occur during normal use. Manufacturers should consider this as not only a patient safety issue, but also a brand equity issue.

Consider a recent FDA safety communication related to off-label use

In a recent communication, FDA informed healthcare providers about the off-label use of surgical mesh in breast surgeries and reiterated that these devices are not cleared for such use:

The FDA is aware of increased use of surgical mesh products in breast surgery. However, the safety and effectiveness of surgical mesh in breast surgery, including in augmentation or reconstruction, has not been determined by the FDA.

The FDA stresses the importance of clinical evaluations to evaluate the safety, effectiveness, and benefit-risk profile of these products when used for breast surgery. There are no surgical mesh products cleared or approved by the FDA for use in breast surgery, including in augmentation or reconstruction.

Use of acellular dermal matrix (ADM) products has gradually increased in the last several years, especially in hernia surgeries to reinforce and support tissue when needed. However, they are also commonly used in breast reconstruction surgeries, for which these devices are not FDA cleared. Such use, therefore, is considered off-label use, and falls within the scope of reasonably foreseeable misuse according to ISO/TR 24971:2020, the guidance for application of ISO 14971.

Types of reasonably foreseeable misuse

According to ISO/TR 24971:2020, there are 3 types of reasonably foreseeable misuse:

1. Use-error: slip, lapse or mistake
2. Intentional acts of misuse
3. Intentional use of the medical device for other (medical) applications than intended by the manufacturer (also known as off-label use)

Use-error, therefore, is only one aspect of reasonably foreseeable misuse. Generally, this refers to unintentional errors that can occur due to poorly designed user interface or inaccurate, incomplete or ambiguous instructions for use. The purpose of usability engineering process, per IEC 62366-1, is to identify, assess and mitigate the risk associated with these use-errors. It is very difficult, if not impossible, to identify the other two types of misuse in these studies. As a result, risk associated with intentional acts of misuse, and intentional off-label use remains largely uncontrolled.

Identification of the reasonably foreseeable misuse(s) should begin early as part of the use-error risk analysis. Once an initial outline of the indications for use statement is available, it should be fairly straightforward to identify some of the potential misuse(s) of a medical device.

As an example, 3 of the potential misuse(s) related to a recently cleared device, GI Genius are shown in the figure below:

Examples of misuse(s) shown in this figure can be classified in the 3 types of reasonably foreseeable misuse listed in ISO/TR 24971:

1. Intentional act of misuse: endoscopist does not use clinical judgment and assumes that a polyp is not real since it is not flagged by the software
2. Intentional use of a medical device for other medical application not intended by the manufacturer (off-label use): endoscopist uses the software to make decisions when the detection location is not suitable for white light endoscopy
3. Use-error: endoscopist is tired and misses a true polyp detected by the software

Consider these best practices

The intent of ISO 14971 requirement for identification of reasonably foreseeable misuse is to consider hazards that may be present when a device is used in a manner other than that intended by the manufacturer.

The challenge for device manufacturers is that they do not have a lot of risk control options through safe design of the user interface or protective measures to manage the risk(s) associated with intentional acts of misuse or off-label use. However, they are still responsible for the overall safety and effectiveness of their devices throughout the lifecycle.

Second, it is not always possible to foresee these intentional acts of misuse and off-label use, especially during the design and development process. We don’t know what we don’t know!

Here are a few best practices to consider in addition to those applicable to use-errors:

1. Identify reasonably foreseeable acts of misuse during usability studies
2. Monitor off-label use during post-market surveillance
3. Consider targeted actions to mitigate the impact of misuse

In conclusion

Managing risk(s) associated with intentional acts of misuse and off-label use is challenging. This is because device manufacturers do not have any direct control over such misuse. However, it is important to actively identify such misuse in the risk management process throughout the device lifecycle to ensure its continued safety and effectiveness.

Deliberate misuse of medical devices, even when there is no malicious intent, can and does frequently lead to serious injury and death. Manufacturers should consider this as not only a patient safety issue, but also a brand equity issue. They should be very vigilant and take targeted actions when they become aware of widespread misuse of their devices.

Read the full article here to learn more.

References

1. FDA letter to healthcare providers - Labeling updates for BD mesh products, 9th Nov, 2023.
2. DEN200055: GI Genius - Gastrointestinal lesion software detection system
3. Let's Talk Risk! newsletter