User requirements for IVD devices are derived from the needs, intentions, and actions of the users of the device. The key users of IVD devices include the operators and handlers of the device or materials. Depending on the situation, these users may include lab workers, healthcare providers, and even laypersons. However, those that receive the IVD results and act on behalf of the patient—such as physicians, nurses, and ambulance workers—can also be considered users.

Understanding the requirements of each of your device’s users is the first step towards developing system requirements. When formulating individual user requirements, it is essential to identify the relevant user groups, tasks, conditions, and goals within the scope of the user.

IVD device-related user requirements should outline the user/system interaction parameters and the use-related quality requirements for any task outcomes.

The FDA specifies user and system requirements as the design inputs to a medical device; however, this requires the definition of an appropriate “intended use” by which feasible requirements can be formulated. The FDA also specifies guidelines for intended use. Following these definitions, system specifications can begin to be outlined and design outputs can be considered. Therefore, it is paramount to not only define user requirements, but also the intended use of the IVD device.

For clinical diagnostics, the identification of user requirements relies on defining what the FDA calls the product’s intended use: what you tell your customers the product can and cannot do, and who it should be used for. Intended use is sometimes referred to as the “product label” or the “product claims.”

You’ll also need to specify the indications for use, which refers to the disease or condition the product is used for, including the type of patient. A careful analysis of what exactly your product is used for and what the clinical question is to be addressed will help you write an intended use statement that accurately reflects the clinical scenario and risk level.

TL;DR: the FDA’s intended use and indications of use for medical devices outline the device’s general and specific purpose. This regulatory framework helps bring the device’s user requirements into focus.

Let’s talk about how to generate a detailed outline of user requirements for your IVD device development project. It begins by understanding the three types of requirements: technical, business, and regulatory.

Technical requirements are the basic needs associated with the product’s use. Does it accomplish the primary task for which it was invented? Does it do so with appropriate performance characteristics, (e.g., specificity, sensitivity, time to result, clarity of result)? Does it fit in the lab space or clinic where it will be used? Does the operator’s education and experience level ensure proper operation of the product?

Business requirements are the practical and managerial considerations customers will need to consider when evaluating your product, particularly those with economic consequences. For your IVD device to be adopted and have the opportunity to improve user experience compared with the test(s) it will replace, it needs to be clear to the customer that switching to it will make economic sense and will improve organizational efficiency. Changing the status quo is difficult for most organizations, and more so in the healthcare industry where updating and documenting alterations to clinical routines can represent a daunting obstacle.

Regulatory requirements are the product’s characteristics, development, and production methods, and the company or site certifications needed to make a product that’s consistent with all legal, regulatory, and industrial standards. The FDA’s “design control” framework for development, ISO 9001 standards, and CLIA certification are all examples that fall into the category of “regulatory” requirements a customer will expect you to achieve. Regulatory requirements are important to consider as part of your IVD device development project.

The FDA provides a benefit-risk analysis for all stakeholders associated with medical devices, which sheds light on technical, business, and regulatory considerations for manufacturers and consumers of medical devices. The FDA also offers pre-submission consultations on the basis of required regulation standards for manufacturers intending to submit medical devices for approval.

However, the process of gathering and defining technical and business requirements may require an in-depth investigation into the intended healthcare market sector at hand. Furthermore, the CDC provides an outline on how to conduct such a market research to identify the technical and business requirements within the scope of medical technology.

(Examples of how to form detailed lists of requirements are presented later on in this blog.)

One important thing to remember for any IVD device development project is that there are many types of users to consider. In addition to the “primary” and “secondary” users discussed in the beginning of this article, it’s helpful to consider the requirements of others that may be involved. This includes those involved in purchasing the product, those who warehouse it, and so on. Each point of interaction plays a potential role in defining the device’s user requirements.

For a thorough grasp of user requirements, start by thinking about how your product will be used (e.g., by whom, and in what setting?) to establish the product design framework.

This framework incorporates traceability so that every element of the process, such as design inputs, outputs, verification, and validation, can be traced back to a known user need. In other words, the user requirements and desired performance of the product define its complexity. The FDA’s “design control” framework associates closely with ISO 9001 quality management standards in regard to medical device design. This standardized development framework ensures that the product’s user requirements are documented and kept in mind at every step of the development process.

The process begins with the definition of the intended use of the IVD device and is followed up by the design inputs. These include the user and system requirements that lead into the initial system specifications. Next, the technical requirements of the design outputs are formed and reviewed. Verification processes are carried out to ensure that the relevant specifications are met, such that the design outputs achieve results outlined in the design inputs. Verification examples for IVD devices may include stability studies, temperature calibrations, and environmental monitoring. Additionally, the needs and requirements of the users are validated to ensure that the device satisfies such requirements to keep the user in focus. For IVD devices, validation may be carried out in the form of a clinical evaluation, whereby competitor devices are compared and contrasted to observe benchmark results. Finally, all documentation will be kept within a design history file for future reference.

Now that we have considered how the FDA interpret the intended use, potential requirements (ranging from technical details to regulatory authorities), and even the product development framework, we can form a detailed list of specific requirements to enable your IVD device development project.

1. A critical first step for your IVD device development project is to determine the problem your product will solve:

• Why is the IVD device needed?
• What will it do?
• How will it accomplish its usage goal?
• At what point in the patient’s clinical course will it be helpful (e.g., predisposition, screening, diagnosis, prognosis, therapeutic response prediction, monitoring)?
• Where will it typically be used (e.g., provider office, hospital, in-home)?
• Who will use the product? What is the user’s expected skill level?
• To validate your initial assessments of these questions, it’s best to review and evaluate the market. What are the trends and competitive products? What does customer research tell you? Given your patent status, how differentiated will your offering be? Does this open up a new user type with new requirements?

The research should be carried out within the relevant healthcare sectors and can be obtained online or offline via surveys, interviews, focus groups, case studies, and context analyses.

2. Based on the data collected during these assessments, define your user or users:

• Will the product be used in a laboratory or in a point-of-care setting (e.g., physician office, clinic, hospital)?
• What level of training and expertise will the user have in each relevant setting?
• Characterize the business objectives of the organizations that are your target customers. Are they looking for a product like yours to save them time? To improve the care they can offer? To differentiate them from other providers? To save them money?

Any of these expectations will affect the user requirements. Summarize the overall market needs, and outline the use case for your product with as much detail as you can.

It’s vital for IVD device product managers to consolidate market research data to define the user or users of the IVD device. The product manager should also take note of any relevant user insights, behaviors, and opinions of similar IVD device designs and their usability outcomes. This understanding will provide design guidance when formulating future analyses and user requirements.

3. Perform a functional analysis. This consists of “walking through” various scenarios of product use, imagining the steps in chronological order throughout the product’s entire life cycle. Begin with your approach to sourcing raw materials and the manufacturing process. How will user needs influence the choices you make, or the choices you have, at this stage? The customer becomes directly involved during the ordering process and is naturally affected by your distribution and customer support choices. How can you best tailor these to user requirements? Afterwards, which steps represent the important functions critical to operation? And which steps have the potential to cause harm or damage? These can be construed as product requirements.

4. End-user implementation of the IVD device is, of course, at the center of the experience. This is where most of the requirements will be at play. We’ve discussed most of these factors already, such as training for users, changes in clinical workflow, and total time and throughput. Due to greater environmental awareness, one factor that has emerged recently is the disposition of used devices. Diagnostics manufacturers can help their customers think through the practical considerations involved, given the complexities involved with human biological material. Will the product be recyclable through the conventional waste management streams or require incineration due to a risk of contamination? What precautions does the lab or clinic need to take? In theory, your company could carry out a recycling program of its own, with customers returning some or part of the device to your facility. This could be a differentiator, but you would need to carefully design and test the return-for-recycling process and develop a plan for managing material that is shipped back. In many cases, recycling may not be practical, but providing recommendations on safe disposal for consumable IVD products is a worthwhile element in the launch plan.

5. Finally, evaluate whether the intersection of functional-analysis requirements and the more general user requirements (e.g., process, performance, safety, cost) results in additional requirements you’ll need to address. For example, if there is demand for a used product to be returned to your company for recycling, what will that recycling program cost your company, and how does that cost affect the overall price you’ll have to charge the customer. What’s the interplay of price and recycling? Of testing throughput and the number of devices you ship in each box? Look at how a small change in one part of your product’s life cycle affects everything else downstream, and potentially even changes assumptions upstream. This may enable you to anticipate and address problems before they arise—setting your IVD device development project up for success.

As simple as it sounds, understanding user requirements in detail is a critical part of your IVD device development strategy and is the foundation of your go-to-market plan. The more thoroughly you define your anticipated users, examine their use context, and explore all the possible needs and expectations they may have, the more completely you can prepare to provide them with a product that not only meets but exceeds their expectations, and becomes a market success.

TE develops and manufactures life science and diagnostic products, including IVD and companion diagnostics. We help our clients quickly turn their technologies into user-friendly, cost-effective, and clinically validated commercial products of quality through a collaborative approach. Our in-house usability testing group and clinical research organization ensure that your product is optimized for the benefit of the end-user, your organization, and regulatory stakeholders.