Developing a medical device requires sensitivity to the delicate balance between usefulness, usability, desirability, and manufacturability. Every medical device must be useful (meet a need) and usable (easy to understand and manipulate properly) in order to gain regulatory approval. The elements of desirability (customer appeal) and manufacturability (efficient and reliable production processes) must also be woven into a medical device’s identity to satisfy business objectives.
Many stakeholders must be satisfied during the development of a new medical device. The term “stakeholder” refers to a person or group having the ability to affect or be affected by a development team’s actions. The priorities of designers, engineers, marketing team members, manufacturing representatives, regulatory specialists, and end-users must be considered simultaneously from inception to commercial release to create a complete story. All stakeholders share common expectations of product quality, safety, reliability, and dependability. Each has a different definition of how these are expressed and measured, making the development process complex and multi-faceted.
An integrated product development process that truly combines Human- Centered Design principles with a solid Design for Manufacturing (DFM) and Design for Assembly (DFA) philosophy will simultaneously address usefulness, usability, desirability, and manufacturability. When handled properly, the probability of a product’s success will be dramatically improved. (See Figure 1)
What is Human-Centered Design?
A Human-Centered Design approach includes the professional disciplines of Design Research, Industrial Design, and Human Factors Engineering. These disciplines all strive to serve the needs of a product’s end user, but they require different skill sets and approaches.
Design Research activities are typically conducted at the front end of a development cycle in order to establish a firm foundation for future design work. These activities are included to discover the needs and dreams of end users, uncovering attributes that will resonate with them on an emotional level. Common Design Research methods include targeted interviews, contextual observation (i.e., witnessing a surgical procedure in an operating room or shadowing a diabetic patient through their daily testing and insulin injection routine in the home), participatory workshops, analogous product benchmarking, and trend tracking. These processes allow a crossfunctional development team to appreciate circumstances, environmental conditions, and user expectations in an effort to identify design opportunities. Discoveries made through Design Research inform the development process, improving the likelihood of success upon market introduction.
Shown in Figure 2 are participants interacting with block models during a participatory workshop. The block modeling toolkit was created to enable quick 3D expression of ideas during exploratory sessions. Users can quickly attach building blocks to a base, creating a tangible representation of a potential medical device to accompany sketches or verbal descriptions. Buttons, dials, or connectors may be attached to a block model to represent user interface touchpoints and stimulate conversation.
Industrial Designers build upon the solid foundation of Design Research, translating insightful discoveries, product performance goals, and marketing objectives into tangible concept directions. Product form, user interface, ergonomics, aesthetic detail treatment, material selection, and manufacturing approaches are all considered during the Industrial Design phase. The process typically begins with collaborative brainstorming, involving a cross-functional team and leveraging the talents of multiple professional disciplines. Through an exploratory and iterative methodology, In dustrial De signers narrow their focus to a manageable set of conceptual embodiments that may be evaluated through illustrations, preliminary CAD models, and physical prototypes.
Human Factors Engineering (HFE) methods are applied throughout the development cycle to mitigate productrelated safety risks and make design decisions. The FDA and other regulatory organizations expect HFE activities to be included throughout the design phase to control risk and ensure product effectiveness. HFE activities may include testing of early concepts with representative users, usability and product handling studies, and final verification/validation studies to meet regulatory requirements. Proper planning, execution, and documentation of HFE practices throughout the development process should streamline the submission process for regulatory approval.
Human-Centered Design activities may be scaled to match the program requirements and objectives. Small-scale efforts may include a brief definition of basic user profiles, fundamental contextual influences, and general market space dynamics. Large-scale efforts may involve additional activities such as indepth user interviews covering multiple geographic regions, co-creation of conceptual mock-ups with potential users, exploration of multiple product embodiments through a detailed Industrial Design phase, and a series of usability studies with representative users handling functional physical prototypes. Regardless of the scope and scale of the program, a well-rounded design and engineering team will keep the needs of their end user(s) in mind at every phase of the product development cycle.
The Human-Centered approach is not limited to a single phase, nor is it a standalone module that can simply be attached to the front end of a program. It needs to be embedded into the cultural fabric of an organization in order to be effective.