Most device manufacturers find the concept of design control confusing. However, design control is better understood now as a result of better structure. The foundation for every product quality is the design process. Similar to a building, the better the foundation, the lesser the risk of collapse. In terms of design, the final product is dependent on the design process.
The design control process can be implemented for medical devices, manufacturing equipment, and operation, and software systems can make use of a similar process.
Below is a diagram of the waterfall system of design.
Waterfall Design System
The diagram depicts a simplistic version of an approved FDA control guidance. The design is typically more complicated due to several elements developing at the same rate. However, the waterfall diagram does serve the purpose of aiding understanding of the operations of the design process.
Common Mistakes in Design Development
One of the prominent mistakes to make is to assume that design control is the same thing as the development process. Although, the development process is a vital part of design control, a more accurate description for design control is to envision it as a lifecycle.
By picturing design control as a lifecycle doesn’t mean that design control will cover requirement for feasibility or marketing. While these processes are vital to the product development process, regulations are in place to monitor product design rather than concern itself with the success of the product in the market. Regulations are more about the safety of the design product instead of the general welfare of the business.
It is important to differentiate between the design input requirement and the marketing requirement and feasibility studies. The design input requirement is also known as the product concept document.
A common problem that most organization face is the approval of documents. There is always a reluctance to approve product design documents as they have to create a room for change and improvement on the document. However, by maintaining control over the document, the approval process tends to become tedious. The goal of control is not to restrict flexibility but to ensure that every phase of the design process is sync, especially when dealing with cross-functional teams.
Typically, approval can be given for revision 1 of a document with To-Be-Determined (TBD) values in certain sections. Meanwhile, teams can start preliminary drafts for the second revision of the document. Subsequent sections will address the core elements of the design control process. However, implementation of the process will depend on the following;
- The maturity of the company.
- Product complexity.
It is worth noting that most organizations prefer to breakdown these processes into individual (SOPs). But, it is possible to have a document that covers all the requirement of several elements of the design and development control process.