Design Control for Medical Devices

What are the Two Types of Design Control Models?

FDA 21 CFR 820.30 stipulates the guidelines for design control for medical devices. Applicable to medical device manufacturers, design controls are used in the medical device development process. There are two main types of design controls that can be used as elaborated below:

• The waterfall model follows a logical sequence of phases or stages. The model follows a traditional or linear approach that begins with requirements and moves to design implementation. In this method, the requirements are developed and a device is designed to meet those requirements. Upon completion, the design is then evaluated, transferred to production, and the device is finally manufactured. In practice, feedback paths would be required between each phase of the process and previous phases, representing the iterative nature of product development. The waterfall method is considered a useful tool to introduce design control. It is applicable to manufacturers focused on developing simpler devices.

• A concurrent engineering model involves both production and service personnel throughout the design process, assuring the mutual optimization of a device’s characteristics and its related processes. It helps organisations focused on simultaneous development and promotes changes. This model takes a more evolutionary approach to design. While concurrent engineering’s primary motivations are shorter development time and reduced production cost, the practical result is often improved product quality.

Medical Device Design Control Guidance

Design control guidance for medical device manufacturers is an important component of safety management as it helps ensure the safety and efficacy of their products. It includes a systematic and well-documented approach to product development. Key elements include:

• Defining design and development procedures
• Establishing clear design inputs and requirements
• Conducting risk assessments
• Maintaining comprehensive design history files

Regular design reviews and verification and validation activities are essential to confirm that the device meets its intended use and performance criteria. Managing changes and conducting rigorous design transfer processes are crucial for a seamless transition from development to manufacturing. Post-market surveillance and feedback mechanisms help manufacturers continuously monitor and improve their device designs based on real-world performance and customer feedback.