A reflection on my experience in medical device development, and how we can move Human Factors beyond compliance and toward greater impact.

Introduction: ‘Carrot’ and ‘the Stick’

How much time, effort and budget do we waste on conducting studies we don’t believe in? We’re ticking boxes: testing devices that we know could be better; testing user manuals that we know often go unread; rationalising use error; and debating with regulatory authorities. We argue with business leaders, “the regulatory authorities are not accepting our validation report because of use error relating to the device design; not the test method or because we so happened to recruit a sample of ‘incompetent’ participants”.

What if we could break the chain? What if we could convince medical device and pharmaceutical businesses to invest in Human Factors (HF) early in device development? What if we could feel confident in the device design before going into a validation study? Can we shift our valuable time, effort and budget towards proactive activities?

As a HF Specialist in the medical device industry, I carry two hats: my 'commercial' hat, and my 'regulatory' hat. I frequently refer to these as a 'carrot' and a 'stick'. In this article, I discuss the importance of both in designing safe, effective and successful medical devices.

In medical device development, HF is frequently regarded merely as a regulatory tick box. Yet, regulatory approval alone does not ensure usability, safety, or real-world success. Reports indicate that about 33% of medical device incidents reported to the US FDA are due to use errors (Shaheen et al., 2020). Imprecise collection of post-market data and a culture of lawsuits, lead to under-reporting of use error. With technological advancements and an ever-increasing focus on home healthcare, this percentage may increase further still.

There are numerous commercial benefits from the application of HF: lower training demands, increased productivity and user satisfaction. These factors can be rolled into a healthcare economics analysis and can lead to users 'vouching' for one system over another during procurement conversations. Having said this, the commercial benefits are more difficult to quantify than in consumer-driven sectors. We struggle to argue that user experience directly affects procurement decisions; the NHS is the customer, and not the clinician or patient. I nonetheless believe that we can do more to identify commercial benefits of HF and leverage them as the motivational ‘carrot’ we need to go beyond the regulatory requirements.

Why Go Beyond Mere Compliance?

There has been significant progress in HF adoption since the release of IEC 62366-1:2015 and the FDA’s Guidance, “Applying Human Factors and Usability Engineering to Medical Devices”, released in 2016. MDR now mandates application of HF for all new submissions, and a post-market analysis for devices on the market prior to 2015.

The regulations call for HF Validation Testing (use testing) on new devices. In theory, a manufacturer can conduct such testing on a device that has had no HF input during development. HF Validation testing is more like a court case than an exam: The manufacturer states whether use errors are acceptable, given the residual risk, and it is for the regulatory authorities to agree or disagree. In my experience, the level of scrutiny is inconsistent from the FDA, and too surface-level from other authorities. It's no wonder that we hear from clients, “I haven’t had submissions rejected so far; why implement Human Factors now?”.

Design flaws that are deemed ‘acceptable’ can lead to significant problems post-market: poor user adoption, high error rates, recalls, and reputational damage. To give an example, a system's accessory meant that the critical alarms were not reliable, but this was deemed acceptable because other systems had the same solution, and because on-device labelling stated that the clinician should check the system every few hours. To improve this, HF was applied early and throughout development of the next generation system and ensured the system could detect this critical alarm state when used with the accessory.

Going Beyond the Requirements: Practical Strategies

Project timelines, resource and budgets are a constraint on meeting the regulatory requirements, let alone going beyond them. What is the root cause behind this? Here are some suggestions:

1. Low understanding of the commercial benefits.

2. HF is often not considered during early-stage project planning.

3. HF is often considered a validation activity, not a design activity.

4. Low awareness of the positive correlation between successful validation testing and a user-centred design process.

5. Low understanding that mitigating use issues by design is far more effective than labelling/training.

6. HF research and simulated use testing can be expensive.

Once we understand root causes, we can begin to identify solutions:

1. Engage Executives and Commercial Teams: Changing a company's culture is notoriously difficult, but we can find key stakeholders who can champion HF with us. Leverage market research to provide business leaders with evidence-based ROI of usability. Learn from consumer sectors, who recognise usability as a commercial advantage.

2. Early-Stage Human Factors Integration: When we have a seat at the project planning table as a project kicks-off, it is easier to schedule activities and request budget for them.

3. Meaningful Gate Reviews: Work with project management teams to include usability milestones into stage-gate processes. If resource is a bottleneck in meeting milestones, then you have an objective justification for increasing headcount.

4. Proactive Risk Analysis: When conducted early, identification of use error, understanding of clinical consequences, and prioritising critical tasks can streamline a project, by providing greater opportunities for design changes.

5. Use a greater variety of HF tools and methods: There is a heavy emphasis on simulated use testing, and it is the gold standard. However, there are many other methods to identify use error and discover/design mitigations that would be frustrating, and costly, to find during use testing.

Collaboration: Bridging Industry and Healthcare

Those working in Healthcare HF have invaluable insights into clinical workflows, environments, and patient interactions that device developers might overlook. In the medical device industry, we struggle to gain access to clinical environments. The logistics, scheduling and ethics processes, mean that contextual inquiry is expensive, and the findings arrive too late; the project has progressed, and the system design has already become too fixed.

A diabetic foot ulcer project clearly demonstrated how contextual insights can positively affect design. Desk-based research showed significant patient non-compliance with clinical recommendations. Interviews with clinicians found that they already have too many systems, and that they don't have the tools or the time to be continually monitoring non-compliant behaviour. By integrating these behavioural and contextual insights, we created a solution that encourages patients to engage proactively with clinical guidance and provide them with simplified, insightful data for a more informed conversation with their clinicians. 

In contrast, another project highlighted the dangers of ignoring organisational factors. A logistics-tracking system designed without HF research failed because it didn't align with healthcare professionals’ workflow for the same reasons; they already have too many systems and not enough time to log in to record their device usage. Effective solutions must address organisational aspects—such as clinical culture, leadership support, and resource allocation—that profoundly influence product acceptance and use. I wonder if those in the healthcare sector can help?

For the full video of Reece presenting on this topic at the Chartered Institute of Ergonomics and Human Factors click here: