Eugene Canavan, from award-winning design & innovation company Design Partners, explains how it puts people at the heart of its device design
Human factors engineering (HFE) is about designing for people. It seeks to recognise human capability – both mental and physical – and design solutions around individuals making the most of that capability. Design Partners product development ambition is to elevate human potential, making life, work and society better and safer by combining design, engineering and HFE. Embedding and integrating human factors into our design and engineering capability is key to this ambition.
When defining medical device and healthcare solutions, documenting usability is a regulatory requirement. This aspect is focused on risk reduction, safety and ensuring the solution is optimised for use. Deployed correctly, HFE will be present throughout a product development life cycle to meet regulatory requirements, but the true value of an integrated HFE process to a development team is much greater.
Benefits of HFE
People; The process is about optimising human cognitive and physical capability, so it’s appropriate that users are considered first. Understanding the end user is essential to make the most of their capabilities. The HFE process maintains a user perspective throughout, from early engagement with users and key opinion leaders, by way of methodologies such as interviews, workflow analysis and contextual enquiry field work. Inherent in the process is understanding user populations, their respective tasks and workflows, in the context of the their working environment.
Ambition; Have you ever wondered during a project if you are doing the right thing? Is the ambition of the project compromised? Is this the right solution for the market? When development projects present technical or mechanical challenges prototyping is a common activity at defined points in the project. The HFE process is no different, as testing early and often with users helps optimise and de-risk the human element. User testing confirms the ambitions and goals of the project are being met.
De-risk; The true value of the HFE process is to consider and optimise for the human component within a system. Understanding this human component in real-time gives a product development team insight that is actionable and implementable. User safety is a central critical element of this. HFE usability standards HE75 and ISO-62366 are designed to be used in conjunction with the medical device risk management standard ISO-14971. The HFE process actively manages risk related to usability and workflow.
Cost containment; Understanding the human component in real-time across the development cycle ensures you are solving the correct problem. It’s easy for a project team to go off on a tangent and work diligently until reaching a dead end. In our experience project teams and management highly value the reassurance, insight and data that usability testing delivers, keeping the project team on track, focused and motivated. Failing early is positive, failing late will be costly –in both time and resources.
The process
A product development process will generally have five or six key phases, starting with research design to set the project up for success with a clear definition of product requirements. This is followed by conceptualising to answer the product requirements, followed by iterative development to perfect the solution and eventually, detailed design, where a full specification for production is defined.
A characteristic of projects moving is that exploration is wide at the beginning but becomes more focussed, narrowing to an optimised solution. The HFE process follows a similar path as every stage of the product development life cycle will have usability-centred input and output. While there may be an HFE lead in the project team or an outsourced HFE consultant, HFE activities should engage the full cross functional team at each stage, to maximise its benefits and promote the integration. Having HFE as a standalone function, may serve to meet the regulatory requirement, but will negate the true benefits HFE can bring to the product and the project team.
Placing the end user at the centre of new product development rather than the technology, allows a true understanding the their needs, behaviours and environment; critical to creating meaningful product experiences. This is achieved by employing research mythologies such as VOC interviews, contextual enquiry or ethnographic studies. Having the cross functional team engage in user research is key to building an understanding of the user, which creates novel, relevant and user–centric device solutions. Usability research feeds the concept phase and provides real insight into technology development and the complete product ecosystem. The outputs from the concept stage can be used for formative usability tests.
A well-defined formative test protocol with clear criteria for success is essential, with testing early and often this does not need to employ large numbers. Formative testing should become more rigorous and focused, with participant numbers increasing as the project progresses. The outputs from formative testing should be concisely documented, be actionable and implementable. The formative process is designed to verify project direction and provide insight-rich data for iterative refinement. This maintains an end user perspective throughout the problem-solving stages of the project. Formative usability testing builds to a conclusion, moving into summative testing following design freeze.
The execution of a summative test is a validation of the usability work completed in the project and a demonstration that the system is de-risked for use. The summative test is a representation of actual use in the marketplace, including training with supporting materials expected to accompany the product launch. This is the most important and expensive phase of the HFE process so it is essential that the test protocol is robust and executed by an experienced moderator. When unexpected issues do arise, it is critical that the moderator uncovers the reasoning behind the issue. Retrospective interviews with the participants are key here as they capture user perspectives and account for usability aspects that may not have been considered in the test protocol. The subsequent summative report is the conclusion of the HFE process. This report is the primary evidence to regulatory bodies that the solution is optimised for safety and intended use.
Characteristics of an embedded and integrated HFE process
Early and continued application of the HFE process increases the likelihood of meeting user needs, bringing commercial advantage and creating better performing solutions. An embedded HFE process will have the following characteristics.
- End-user perspective and needs are maintained through the process
- Design decisions are informed by end-user interaction tasks and needs
- HFE activity is tied to the overall development process
- HFE activity is tied to the design controls and risk management
- Usability problems are addressed as they arise and not at the end
- HFE process provides for an iterative optimisation process
- The results of HFE activities are actionable
- The HFE plan is defined and is linked to the project design history file (DHF)
HFE is a regulatory requirement but applied well, it is also a strategic product development and cost containment tool essential to commercial success. Let’s harness the power of HFE to provide solutions that elevate human capability.
