Design Controls for Medical Devices

What are the Two Types of Design Controls Models?

FDA regulations under 21 CFR 820.30 design controls medical devices stipulate the guidelines for design controls applicable to medical device manufacturers. These controls guide the entire development process, defining how design control phases in a medical device are planned, executed, reviewed, and transferred to production. There are two main types of design control models that can be used, as elaborated below:

• The waterfall model follows a logical sequence of phases or stages. This traditional, linear approach begins with requirements and progresses through design implementation. In this model, requirements are clearly defined, and the device is designed to meet those requirements across each of the design control phases medical device development requires. Upon completion, the design is evaluated, transferred to production, and the device is manufactured. In practice, feedback paths are often required between each phase and earlier stages, reflecting the iterative nature of product development. The waterfall method is commonly used to introduce design controls and is well suited for manufacturers developing simpler medical devices.

• A concurrent engineering model involves production and service personnel throughout the design process, ensuring the mutual optimization of a device’s characteristics and its related processes. This approach supports overlapping design control phases for medical device development, enabling simultaneous design, validation, and process planning. It promotes flexibility and continuous improvement while taking a more evolutionary approach to design. Although the primary drivers of concurrent engineering are shorter development timelines and reduced production costs, the practical outcome is often improved product quality and compliance.

Medical Device Design Controls Guidance

Design controls guidance for medical device manufacturers, aligned with 21 CFR 820.30 design controls medical devices, 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, evaluate, and improve their device designs.