Human Factors Engineering for Medical Device Design - Anticipated Trends

# Background

Human Factors Engineering (HFE) should be an integral consideration for all medical device manufacturers throughout the design and development process, not only to secure FDA approval but also to cater to user and patient needs. The scope of HFE involvement is determined by regulatory risk classification, potential harm levels associated with device use, and product complexity.

Rather than treating HFE activities as a final checklist item, it's essential to integrate human factors processes throughout the development continuum. If HFE is only addressed as a regulatory requirement during the latter stages of design, there's a risk of uncovering usability and safety issues that demand costly redesigns and schedule delays. This not only affects financial aspects but also provides competitors an advantage.

The pivotal question is when to involve HFE practices in the design/development cycle. This article examines HFE practices and highlights that early integration can identify crucial product safety and usability concerns, leading to efficient development timelines and regulatory compliance.

HFE is more than a mere focus on regulatory approval—it's a fundamental process that should be integrated into the entire product development cycle, involving project management and system engineering from the project's inception. According to the FDA, HFE revolves around understanding human-technology interactions and how user interface design impacts these interactions, encompassing medical devices used by both trained practitioners and patients at home.

In the context of medical device development, HFE defines user-device interactions, including task analysis, to identify usability challenges and associated usage risks. This process generates design inputs that guide user interface features to prevent critical use errors.

# Application of HFE in New Product Development

The ideal point to involve HFE practices is as early as possible in the process. Early involvement enables methodologies like contextual inquiry and comparative studies to develop relevant design inputs during systems engineering. Usability engineering plans should be tailored during early phases, like feasibility assessment, by cross-functional teams.

The Usability Engineering (UE) file within the Design History file should document rigorous HFE processes, including usability engineering activities and design inputs. Usability specialists can conduct studies in real usage contexts, observing behavior of clinicians and patients, allowing for real-time insights and questions.

Neglecting early HFE involvement and relying solely on later validation tests increases the risk of discovering use-related errors post-design freeze, leading to expensive design changes and commercialization delays. Proactively evaluating HFE early in product development boosts confidence in final testing performance.

# Regulatory approach

The FDA assesses medical device safety and efficacy comprehensively, necessitating examination of users, scenarios, and environments. A thorough HFE analysis and usability testing plan should incorporate these elements, including a use failure mode and effects analysis (UFMEA) that outlines use-related risks.

Discussions within the HFE community explore the need for a comprehensive use-related risk assessment tool, distinct from UFMEA, which is more focused on reliability rather than usability. This assessment tool, referred to as URRA, should address parameters such as use task description, potential use errors, clinical harm description, harm severity, task criticality, risk control measures, and validation methods.

In a constantly evolving healthcare landscape, the FDA's processes and policies adapt, with industry input playing a crucial role. Engaging with the FDA early allows alignment on HFE approaches before device validation submissions.

In conclusion, integrating HFE into medical device design during early development phases, such as feasibility assessment, and considering human factors engineers as partners in the process, reduces use-related and commercial risks. This approach enhances the likelihood of a successful product launch, mitigating last-minute risk factors that lead to costly redesigns and impact FDA validation for launch.

# Trends in HFE

Following are the anticipated trends in HFE.

a. Increased Emphasis on User-Centered Design: The importance of designing medical devices with a strong focus on the needs and abilities of the end-users (clinicians, patients, caregivers) is likely to continue growing. HFE will play a crucial role in ensuring that devices are intuitive, efficient, and safe to use.

b. Integration of Advanced Technologies: The integration of advanced technologies like artificial intelligence (AI), machine learning, and augmented reality can significantly impact medical device design. HFE will need to address the challenges and opportunities presented by these technologies to create seamless and user-friendly interfaces.

c. Personalization and Customization: Medical devices are becoming more personalized to individual patient needs. This trend will require HFE to consider how to design devices that can be easily tailored to different users while maintaining usability and safety.

d. Remote and Home Healthcare Devices: The COVID-19 pandemic highlighted the importance of remote healthcare and monitoring. HFE will need to adapt to design devices that are user-friendly for remote use and can provide clear instructions and feedback to users who might not have direct access to medical professionals.

e. Ergonomics and Accessibility: Designing devices that are ergonomic and accessible to a wide range of users, including those with disabilities or limitations, will continue to be a priority. This might involve considering factors such as user mobility, vision impairments, and cognitive abilities.

f. Data Security and Privacy: With the increasing connectivity of medical devices to networks and the internet, HFE will need to address concerns related to data security and privacy. Users should have confidence that their personal health information is protected.

g. User Training and Onboarding: As devices become more complex, effective user training and onboarding processes will be essential. HFE will need to design devices that are intuitive enough for users to quickly grasp their operation, potentially reducing the need for extensive training.

h. Regulatory Considerations: Regulatory agencies, such as the U.S. Food and Drug Administration (FDA), are placing greater emphasis on HFE in the design and approval of medical devices. Manufacturers will need to demonstrate that they have thoroughly considered human factors and usability in their design processes.

i. Collaboration and Interdisciplinary Teams: HFE involves collaboration between various disciplines, including design, engineering, psychology, and medicine. Anticipated changes include even more interdisciplinary collaboration to ensure that medical devices meet both clinical and user needs.

j. Post-Market Surveillance: HFE doesn't stop after a device is launched. Continuous monitoring and feedback from users will become increasingly important to identify any usage issues or safety concerns and make iterative improvements.