Diagnostic test developers, including clinical laboratories, responded to the COVID-19 pandemic with inspiring creativity to meet patient testing needs. These developers found unique ways to enable clinical testing with remote technologies, such as apps and tools that support telemedicine, and quickly honed test designs to incorporate the rapid emergence of new viral variants.
This innovation is broadly present in diagnostics today, with test developers leveraging technological advances and a deeper understanding of disease to meet clinical needs.
High Complexity Tests In A Highly Complex Environment
Many modern clinical tests have become increasingly complex, and the number and type of user needs that must be addressed in test development have expanded considerably. For example, patients have become increasingly involved in their own health care. Test development now often requires the integration of disparate disciplines, ranging from pathology to artificial intelligence to human factors engineering. Also, clinical evidence continues to rapidly evolve. All these factors add significantly to what is required of tests.
Against this new and incredibly complex landscape, there is a growing need for a systematic approach to designing, maintaining, and improving tests. The design controls framework provides an efficient mechanism to capture customer needs, rapidly iterate test design, and maintain a system to respond to feedback and rapidly improve the product.
We understand that design controls are an important part of this modernization effort. And regardless of the outcome of current legislative efforts, laboratories should consider incorporating design control concepts because they can add value, particularly for complex clinical tests, and help deliver on the promise of innovation in clinical testing to improve patient care.
What Are Design Controls?
Design controls help developers systematically develop products to meet user needs. Design controls are a process that involves prospective planning and discussion to capture specifications for how well the test must perform to be launched.
Some test developers unfamiliar with the design controls process may question how it fits into other product development activities—such as evaluating bench performance, selecting reagents, optimizing software, and performing clinical studies. These developers may believe that it represents unnecessary additional work. Yet, based on our experience, the early stages of design controls—such as planning experiments or listing stakeholder needs—can in fact improve development plans by clarifying the test’s intended users, the patient population, how it relates to other diagnostic procedures, and the risks of false-positive and false-negative results. This process involves comprehensive discussions and decisions about what the test is intended to do for patients.
This up-front work, generally defined as design inputs and risk management, helps to inform what the test needs to do and guides subsequent performance studies to demonstrate that the test works as intended.
The 4 Key Reasons for Design Controls
First, design controls capture test developers’ thought processes in a structured and objective way and therefore help ensure that the test is designed to meet the needs of patients and the expectations of any accrediting or regulatory body. Design controls also create a mechanism for performance improvements to be made over time in a systematic, efficient manner. Although these concepts may be practiced by some test developers in high-complexity clinical laboratories, they have not been broadly adopted.
A second benefit of the design controls process is that it provides a framework for comprehensively capturing stakeholder needs. For example, there may be specific needs regarding results reporting, especially those in integrated electronic health records. Test results should be easily understood by clinicians as well as patients, and test reports should reflect the capabilities and intended use of the test. In addition, many public health organizations, including the FDA, have emphasized the value of patient engagement. Application of design controls can help ensure that these needs are both captured and addressed in product design because these requirements are directly assessed.
Third, design controls are a highly customizable framework for promoting product quality. Design control principles provide developers with autonomy to determine the appropriate level of documentation for their test based on how it will be used and how patients may be affected. Test developers also rely on specific user requirements to define the level of detail of design documentation, which can then be useful for multiple purposes, including efficiently demonstrating performance and serving as the basis for assessing the adequacy of future changes.
Finally, design controls enable rapid innovation. On the surface, systematically capturing specifications and assessing risk may seem like a barrier to rapid innovation. In fact, by creating a documented structure, design controls allow developers to quickly and predictably assess how changes would impact test performance. They may in fact open the door to more rapid innovation cycles.