The role of human factors in product design
Having trouble deciphering the FDA waterfall diagram process for medical device design and development? You’re not the only one.
It isn’t uncommon for medical device companies who partner with us for strategy, design, or engineering services to be overwhelmed by the FDA’s process. Or, more specifically, with how the process is communicated in the FDA’s 5-stage waterfall diagram.
It isn’t always clear what stage a project is in or what next steps the product team needs to take to move the project forward. This uncertainty creates risk.
The medical device design and development process doesn’t need to be messy when working with a medical device design firm.
We decided to create a different, more comprehensive way of looking at the medical device design and development process, and now we’re sharing it with you.
A new medical device waterfall diagram from cradle to grave
The new diagram is a fusion of the FDA’s five-stage design control process and user-centered design.
- It expands to 10 stages to encompass the entire medical device design and development process—not just from user needs to production, but from cradle to grave.
- It incorporates key milestones along the way to mitigate financial and product risk.
- Last but not least, instead of a linear process, our diagram reinforces the iterative nature of design.
The diagram makes it easier for organizations to understand where they are in the process and what resources they’ll need next to be successful.
Why develop our own medical device waterfall diagram?
The FDA waterfall diagram does a good job illustrating the design controls process and the interrelationship of documenting user needs, design inputs, design outputs, reviews, verification, and validation.
But, as a human-centered design firm, we feel the design process described by the FDA waterfall diagram falls short in really capturing the following key items:
1. Design as iterative process.
Design is not a linear process, but the FDA diagram gives an impression that it will be. Successful design should be iterative, so our diagram acknowledges there are often several turns of the crank within each stage.
2. Strategic contribution of other disciplines prior to formal engineering.
Many processes use an approach that is too centered around engineering. Incorporating insights from Strategy, Industrial Design, Interaction Design, and Human Factors are crucial to the overall success of the medical device in the marketplace.
3. Activities along the way.
The FDA’s diagram doesn’t show when specific activities need to occur, such as conducting feasibility assessments and tooling fabrication for first articles.
Stages 1–3: Set a foundation
The first three stages of our medical device design and development process are designed to mitigate the risks of developing a medical product by creating a solid foundation.
Our researchers, designers, and engineers focus on understanding the market, gathering initial user needs, and creating and evaluating multiple product concepts. Meanwhile, our quality department is preparing the design history documentation and documenting design inputs and verifiable product requirements, per FDA regulations.
Stage 1. Business Strategy – We evaluate the desirability, feasibility, and viability of your product idea. We discover if your solution is something customers want, can realistically be built, and will lead to the long-term growth of your organization. These early investigations are key in informing the rest of the design.
Stage 2. Need Finding & Design Planning – This stage involves conducting user research and design process planning. Significant efforts go toward establishing design and development plans while identifying user needs. By documenting this information early in the process our clients will have a head start in mitigating the product risks, aligning the project teams, and compiling the needed records for submission.
Stage 3. Conceptual Exploration and Feasibility – Our multi-disciplinary design and engineering teams will explore ideas and generate product concepts for evaluation. Throughout this iterative stage, we are showing these concepts to representative users to solicit feedback, identifying potential use errors while they can be designed out, and updating our product requirements based on what we learn.
At the end of stage 3, you will have selected a single concept and are ready to progress to stages 4–6.
Stages 4–6: Make it work
Once a single concept has been selected, it is engineered to meet all product requirements, anticipating the manufacturing, assembly, and sterilization methods in mind.
Stage 4. Design Engineering and prototyping – The engineering team makes sure the product can do what the user says it needs to do. We look for creative ways to achieve the desired outputs, such as through mechanical design or material and process selection.
Stage 5. Transfer and Pilot Production – We work closely with our client and client’s manufacturer as they plan and fabricate their tooling, troubleshooting issues that keep features from performing as designed. The design is documented, risks evaluated, and production intent samples can be manufactured for testing.
Stage 6. Design Verification and Validation – The design hardware, electronics, and software are verified. Then our human factors team will conduct Validation and Summative studies on the production-equivalent samples.
At the end of stage 6, you will have prepared the Final FMEA, Risk Management, and Design History files.
Let’s talk about how we can help move your business forward.
