The adage “prevention is better than cure” is often repeated, yet its implications for modern healthcare are still underestimated. In Outlive: The Science and Art of Longevity, Dr Peter Attia and Bill Gifford highlight a critical imbalance in contemporary medicine: we excel at treating acute conditions, but we lag in preventing chronic ones. Lung cancer offers a striking example. While therapeutic advances have improved outcomes, the most dramatic reduction in mortality has come from smoking bans, a preventative intervention rather than a reactive treatment.
This mindset of prevention should be embedded not only in clinical practice but also in the way we design medical devices. In this first article, we examine how preventative thinking can shape the development of risk controls. A second article will explore how use-related risk analysis (URRA) supports this approach.
“Strategy without tactics is the slowest route to victory. Tactics without strategy is the noise before defeat.” Sun Tzu
Designing medical devices demands a strategic, prevention focused approach to reducing harm. Regulatory frameworks reinforce this expectation. ISO 14971:2019 establishes a clear hierarchy of risk control measures, prioritising those that eliminate hazards at their source:
- Inherently safe design
- Protective measures
- Information for safety (e.g., training, labelling)
IEC 623661:2020, the cornerstone standard for usability engineering, echoes this hierarchy and emphasises that risk control is inseparable from user interface design. With that in mind, let’s examine these tactics from least to most effective.
Training
Training is frequently proposed as a remedy for use errors, but it is the least preferred form of risk mitigation. Effective training is not a simple addon; it is part of the user interface and must be designed, validated, and tested with the same rigour as the device itself. More importantly, training does not remove the underlying hazard. Instead, it transfers responsibility to the user, making it a reactive measure rather than a preventative one.
Instructions and Labelling
Instructions for use, warnings, and labelling often serve as the final barrier between the user and potential harm. IEC 623661:2020 requires that such information be perceivable, understandable, and actionable. However, like training, these measures rely heavily on user attention, memory, and compliance. They can support safe use, but they cannot guarantee it; especially in high-pressure clinical environments.
Safeguards
Protective measures, such as needle shields or interlocks, offer a more proactive form of risk reduction. They can significantly reduce the likelihood of harm, but they do not eliminate risk entirely. Their effectiveness depends on correct use, and they may introduce new usability challenges or unintended consequences. For this reason, IEC 623661:2020 emphasises the importance of evaluating safeguards through both formative and summative usability testing.
Designing Risks Out
The most powerful and preferred strategy is to eliminate hazards altogether. This is the essence of inherently safe design. For example, replacing an injectable medication with a transdermal patch removes the risk of needlestick injury entirely. ISO 14971:2019 places this approach at the top of the hierarchy, and IEC 62366-1:2020 reinforces it by encouraging early identification of hazard related use scenarios; before design decisions become fixed.
Regulators expect manufacturers to reduce risks as far as possible, not merely to acceptable levels. When residual risks remain, they must be supported by evidence demonstrating that the chosen mitigations are effective and appropriate. A robust usability engineering process is therefore not optional; it is fundamental to demonstrating that preventative thinking has been applied throughout development.
Looking Ahead
In the next article, we will explore how early use related risk analysis (URRA) strengthens this prevention first mindset and helps teams identify hazards before they become embedded in the design.