Medical Device Link.

PRODUCT DEVELOPMENT INSIGHT

Reade Harpham

Over the next year, the term human factors must become very important to those who develop and market medical devices (if the term is not already). Developers must take a look at some common misunderstandings about the inclusion of human factors into the product development process. And many companies may need to alter their perception of human factors.

David Wourms

FDA wants evidence showing that human factors applications are used as a risk management activity in the device development process. Companies that do not have robust human factors integrated into their development process must consider how to include such applications so that medical devices meet FDA approval.

Donna Pydlek

Initially, the inclusion of human factors criteria may translate into increased development costs. However, the consequences of not implementing human factors could be much more expensive. A device could fail to gain FDA approval or get recalled because of use errors. Worse yet, a company may face litigation based on a lack of human factors. The long-term implications of overlooking human factors bear much thought. Pay now or pay more later?

Beyond the regulatory considerations, however, there is another aspect of human factors: it’s just good business. To be plain, human factors works to create better and safer products. Device manufacturers should consider this aspect of the process as well, and embrace human factors to achieve product success.

Managers make the final decisions on how and when to integrate human factors into development. Therefore, this article also provides managers with the essential facts they need to consider when integrating human factors.

User-Friendly Isn’t Enough

FDA requires the application of human factors as a risk management activity—focusing on foreseeable misuse and how that interaction affects the inherent risk of using a device. The agency’s intent is reduce medical use error. FDA’s focus on safety and error reduction presents a number of challenges, specifically to design firms for which human factors activities revolve only around empathy for the user and ease-of-use designs. This doesn’t mean designers can forget ease to use as a design goal. In fact, the argument can easily be made that working to achieve ease of use in itself can help reduce errors.

Sidebar: Achieving Testable Data

As far as FDA is concerned, however, those issues are secondary to reducing medical use error. FDA needs testable data (proof) that illustrate that human factors were applied to risk management activities in the development process. Gathering such data for FDA requires the performance of human factors activities under scientifically based, testable, and repeatable processes not typically practiced by design firms (see sidebar “Achieving Testable Data”).

Although using human factors to create a positive medical device user experience is sure to impress focus groups and energize marketing, these activities add little or no value unless they also align with FDA’s requirements for risk management and can be fully written into the design requirements. Making it pretty is not enough; you must also make the device safe to use. And although the entire development team should focus on safety, the human factors professionals must zero in on how design decisions affect user safety.

FDA defines human factors in terms of medical devices as “the study of how people use technology. It involves the interaction of human abilities, expectations, and limitations, with work environments and system design.”

It is clear that FDA places emphasis on the application of human factors in medical device design to reduce the risks associated with use. The frequency and consequences of medical device use errors far exceed those occurring from device failures.¹ Therefore, FDA requires that medical device developers use human factors data for risk management to reduce or prevent use-related hazards.

Overcoming Obstacles

Adopting human factors into medical device development provides long-term benefits. However, such changes are likely to involve near-term hazards from those who lack extensive experience in the field or are not up to speed on changing regulatory standards.

As a growing number of design and development firms look to enter the medical device market to offset the exodus of consumer device development, human factors is sure to be one of the disciplines leveraged. However, the definition, planning, and execution of human factors activities vary greatly depending on a firm’s experience with human factors. The manner in which human factors activities are integrated in device development determines the success or failure of market introduction.

Here are some common ideas that can hinder the implementation of or prevent changes to a human factors program.

It’s Too Fuzzy. Technical thinkers can find it difficult to appreciate the subjective nature of human interactions with medical devices. However, these people are invaluable to the processes needed to write measurable specifications. Repetitive use of human factors data helps such personality types adapt to the process.

It’s Just a Passing Trend. Not according to FDA. And if FDA approval is the ticket to the medical device market, it’s time to look at the merits of human factors. Translating the subjective into objective is the synergy of human factors. Those involved must recognize the priority that management places on human factors and acknowledge that the process is here to stay.

Implementing Human Factors

FDA will not tell you how to bring human factors into the development process; it is interested only in whether a company can produce documented evidence of human factors applications. User safety and avoiding use error are of primary importance to FDA. Device development managers, then, must decide how they will implement these activities in order to achieve FDA approval.

Some guidance documents can help. FDA recognizes ISO 14971 as the primary risk management standard for medical devices. When considering human factors, issues including patient safety; reducing, preventing, and correcting use problems; and encouraging industry to focus on use safety have priority. The ISO document was developed for these types of problems.

AAMI is expected to release a new standard later this year. HE-75, “Human Factors for Medical Devices,” is a set of best practices that brings focus and application of human factors to medical device development. AAMI has realized that use-error risk has been consistently overlooked in device development. HE-75 attempts to clarify what makes a user interface easy to use and error tolerant. HE-75 is under review and is expected to be released in the fourth quarter of 2008.

One human factors philosophy to consider is based on William Howell’s 2001 address to the Human Factors and Ergonomics Society (HFES).² During his speech, Howell examined two philosophies to implementing human factors and influencing design, as follows:

• The unique discipline model, which positions human factors as an emergent, independent discipline through which design is influenced directly.
• The shared philosophy model, which promotes human factors awareness, concepts, and approaches through a variety of related design, engineering, and management disciplines.

A blend of these two models can work, especially for companies just beginning implementation. For example, Battelle established a system for which human factors and the applied human sciences exist as independent disciplines. In addition, the firm maintains a body of knowledge and resources recognized as valuable, direct input to the device development life cycle.

Blending enables a firm to leverage a diversity of skills and capabilities from all areas of expertise within a company. It tends to work best for firms that put an emphasis on a shared approach. At some companies, industrial designers act as the human factors experts. And they are, because of their focus on user needs. But industrial designers may lack the scientific, repeatable processes required for design controls and FDA’s satisfaction. Industrial designers are the core building blocks of human factors, but they cannot work alone.

What is interesting is how this process has evolved. Increasingly, the shared philosophy approach is dominating Battelle’s medical device development practice. The reason for this is logical and relatively simple. Once a company begins to acquire familiarity with human factors, it makes sense to widen the goals so that each discipline shares its application. All facets of design and engineering use human factors research in device development. Therefore, they have equal need for the contributions made by each sector.

The shared philosophy approach for the type of human factors information captured, analyzed, and implemented during the device design process results in actionable data. Actionable data provide information that is scientific, repeatable, and testable. The data help build proof so that another engineer or scientist can take action. Actionable data speak the language that engineers and other scientists understand.

Adopting a shared philosophy among all relevant design and engineering disciplines sets up an environment for collaboration. It enables human factors practitioners to understand the needs of the designers and engineers. This includes not only user perception information, but also quantitative human and device performance data that can be used to increase safety and reduce use error. By sharing human factors philosophies and data collection, developers can create devices in which users, equipment, and the operating environment are appropriately matched for optimal, safe, and effective use and performance.

Human Factors and Device Development Teams. Human factors professionals must build collaborative relationships with other design team members, especially project managers and engineers from other disciplines, to convey the beneficial use of human factors data. If these data are not used or challenged at the beginning of device design, use error may germinate. All team members must understand how human factors data affect their work on the device, as well as the work of their colleagues. Collaboration builds respect and improves understanding of others’ design challenges.

Management’s Role

The collaboration necessary to implement human factors in the development process cannot be successful without strong commitment from management. A manager’s language and decision-making process must demonstrate the value of integrating human factors. Design teams invariably model the values they observe in their managers.

Managers must be willing to commit resources to human factors efforts, as well as to openly discuss the changes with development. Discussions of risk management and project time lines with the design teams, it’s an opportunity to discuss the integration of human factors. If human factors involvement is new to your design teams, use every opportunity to reinforce its value.

Managers must decide where in the device development process they will incorporate human factors professionals’ involvement and data. FDA’s concern is about using human factors data to make a safe device and to avoid use error. Managers can choose to use human factors information at the very beginning of the project, in the middle, or closer to the end. But they need to consider carefully where human factors benefit the most.

For Battelle, it is best to include human factors professionals throughout the entire development process. This is an integral part of risk management because potential device error does not always appear in initial device development activity. It may show up in verification or validation testing, or in postmarket surveillance (where it is expensive to correct).

The Human Factors Ripple Effect

Human factors input creates a ripple effect throughout the development process. This discipline does not confine itself to device planning stages. FDA may see red flags if an operating manual contains numerous hazard warnings. It may conclude that these warnings indicate residual risk. FDA may ask whether human factors considerations were included during assessment. In addition, an astute device manufacturer knows that the first document requested in medical device litigation is the operating manual. It is a critical practice to ensure that device manuals incorporate human factors as well as the device.

Marketing professionals can build stronger cases for the sale of a device by understanding the types of human factors usability performed or other safety particulars that would assure potential buyers.

Quality assurance personnel should view the human factors effort as supportive because their efforts to meet quality requirements are frequently intertwined with safety. The human factors’ influence works best when it permeates all perceived boundaries.

Staying Alive in a Competitive Marketplace

Medical devices developed without the benefit of human factors application are at greater risk for use error and could face redesign. No developer wants to end up in litigation. Further, a developer must strive to meet FDA requirements. Managers with their eye on continued success recognize the necessary inclusion of human factors in the medical device development process.

Strong implementation of human factors is a good way to maintain successful product development. It is crucial that device manufacturers use resources, such as HE-75, as they become available. But even more important, companies must develop a culture in which human factors is a continued emphasis.

Reade Harpham, David Wourms, and Donna Pydlek work for Battelle Medical Device Solutions (Columbus), where Harpham is manager of industrial design, Wourms is a principal research scientist, and Pydlek handles technical writing. Contact the authors at harphamr@battelle.org.

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