Designing medical devices requires more rigor than other devices. For example, you need to submit documentation to the Food and Drug Administration (FDA) or Conformitè Europëenne (CE) showing you followed a certain process. Much of this is good practice for any product and can improve your ability to complete designs on schedule, on budget, and with high quality.

First, as mentioned in an earlier blog in this series, make sure you have done extensive market research. You need to fully understand the purchaser and the user, as both will influence the requirements of your device. The results of the market research should be put into a Market Requirements Document (MRD). This document describes the product in the words of the customer or user and documents your findings, so that you can share them with your team and use them to define the various stages of your product feature roadmap.

Second, using the MRD feature roadmap, create a detailed description of the product, which is known as a Product Requirements Document (PRD). This document needs to be written at the Minimum Viable Product (MVP) level, from a technical point of view. The PRD is for engineers to use to create the product, and you want to be sure they don’t have to guess at what is intended. There should be details covering every aspect of mechanical, electrical and software specifications, as well as other applicable areas. If there is a lot of software or firmware, a Software Requirements Specification (SRS) is often used to document it specifically. It is important that every item in the PRD and SRS can clearly pass or fail with a test, since the product must be tested after it is designed. This is called verification testing. The results are provided to the FDA or CE. If the results of the test are ambiguous, it is not a good test or a good requirement.

As with any device, you want to be sure there are no big risks in the design. Are you attempting something that has never been done before or may be impossible? Review the technology with experts. If the design does actually seem risky, do additional feasibility research, design a prototype, or perform testing to ascertain if you can reduce the risk. It is important for you to make this design risk assessment at the beginning of the project so that you don’t realize late in the process that designing the product is actually impossible or more expensive or time consuming than you originally thought. For additional guidance on best practices for medical product design, please visit the Voler Systems website here.

Walt Maclay is the President of Voler Systems and Strawberry Tree, Inc. Walt has over 35 years of engineering management and design experience. He has led Voler to develop an outstanding reputation for quality, on-time delivery, and great customer service by working closely with its customers. He has managed over 200 development projects. Walt has run Strawberry Tree / Voler since 1979 when he founded it. A wide range of products and test systems have been developed including: Wearable devices, home health, devices for the aging, Medical devices, Aerospace, Industrial and Consumer. Prior to founding Strawberry Tree / Voler, Walt worked at Interdesign, Fairchild, and Texas Instruments as an electronic design engineer.

Walt is a senior member of IEEE and has a BSEE from Syracuse University. He has advised numerous startups, helping them with technical and nontechnical issues.