From the shock of initial diagnosis to living with a chronic condition, patients experience a variety of emotions that may aid or deter from both learning to live with the condition and treating it effectively. Patients embark not only on a physical but also an emotional journey through becoming ill, being diagnosed and learning to manage the disease. This journey has an impact on how a drug delivery system should be designed to ensure optimal use over time.

To design a delivery system that will truly resonate with patients, one must first understand the behaviors and motivations of the intended user groups. To understand the needs and desires of users requires insight into the unique experiences and situations of those users by conducting research that will drive innovation in design and development process to create a solution that works not only for the intended user group in a variety of situations, but also throughout the course of treatment.

At the core of human factors engineering (HFE), and the mitigation of user-based risk, is a commonsense approach that insists on considering design options in the context of how a human interacts with the world. For the pharmaceutical delivery device industry, understanding how HFE defines and evaluates human capabilities is only part of the puzzle. Design experts must also understand that the human condition is not a static state but rather a series of evolutions. Treatment over time constitutes a journey, and by understanding that the needs and desires of the patient will change, human factors experts can reduce user-based error, and control or reduce current and future risks associated with device use.

A Flexible Set of Tools
The FDA has offered recommendations for medical device design optimization through human factors analysis, testing and validation. The methods provide an effective way to understand use-related hazards and optimize how people interact with the technology. Human factors engineering and usability testing boil down to three major components of the device-user system: 1) device users, 2) device use environments, and 3) device user interfaces. Using in-depth statistical analysis, data aggregation and synthesis techniques should yield actionable opportunities for innovation and a thorough understanding of the potential users’ behaviors, motivation and needs.

There are many tools available for use, and human factors experts should start by determining what needs to be known about the user and the device interaction before selecting the best method. Methods include:

• Qualitative: interviews, ethnographic observation, contextual inquiry and concept evaluation
• Quantitative: questionnaires, in-person surveys and user-based performance testing
• Analysis and Synthesis Outputs: affinity diagramming, product adoption road maps, and habits and ideal scenarios
• Human factors/ergonomics: human error and risk analysis, usability testing and heuristic analysis (encouraging a person to use the device on his/her own)

Discovery research, directional and preference testing — as well as usability testing — offer a strong framework for the development process. Through discovery, customers’ needs and desires can be confirmed. Directional research allows users to evaluate product concepts and usability testing helps to ensure that the delivery solution is appropriate for users. For a more robust testing framework, usability can be broken down into four major components. All are inextricably linked in the context of understanding what usability means. They are:

1. Physical abilities: anthropometry (the measure of bodies, such as heights or the size of hands), biomechanics (what can be accomplished physically, e.g. how much weight can be lifted, how firmly something can be grasped), and sensory abilities (vision, hearing, tactile sense, etc.)
2. Cognitive abilities: how people process information, the capabilities of memory, the manner in which humans learn new things, and how habits are developed.
3. State of being: the general health of the expected user, disease states and co-morbidities the patients are likely to be challenged with, mental and emotional states, and motivation for learning new things.
4. Experiences: educational background, knowledge of a particular disease state, and lifelong experiences with objects that will guide behavioral interactions with any delivery system.

Each of these components helps make important connections in the relationship between the user and the device. To get the best data, it is helpful to interview in the proper context. Someone sitting in a conference room will have a different user experience than a stay-at-home mother who is also taking care of an aging parent. Seeing the user in the midst of daily distractions such as children, pets, ambient noise, temperature and lighting, all help human factors experts better understand how the patient will use a device, and the many factors that may affect use. Also, usability may change over time as the patient becomes more accustomed to a device.

In addition, patient needs must be appropriately defined. There are three types of needs that are important to the success of any development program. Different techniques can be used to elicit and discover these needs, which include:

• Expected needs: the obvious ones that are meaningful to patients. Direct observations inside the user’s environment can effectively document these types of needs.
• Expressed user needs: those that are simple for users to articulate. This may be something such as “needing” and requesting a non-slip handle. Think-alouds and other narrative techniques are best to determine expressed needs.
• Exciting needs (“delighters”): things that patients do not think about as possibilities because they may not know what is technically possible. Reaction to emotive stimuli, scenarios and storytelling are ways to elicit emotionally based needs.

To get the richest data, human factors experts must follow the patient on his or her journey — from diagnosis to end of therapy — and then translate the multitude of qualitative and quantitative data into features of a product that will not only provide a patient with safe and effective delivery, but also meet his or her emotional needs throughout the course of treatment.

Understanding the Patient Journey
There are several stages that a chronically ill patient undergoes from the first symptoms of illness. The outline that follows depicts discrete stages in this journey, each of which has an impact on the usability of a therapeutic device.

Initial Diagnosis
For many patients, the initial diagnosis of a chronic condition is both a shock and a relief. Many may respond with anger, depression or even denial, and often approach the need for medication with hostility, fear or anxiety. Learning to facilitate their own treatment can be daunting, and they may suffer from symptoms that impair their ability to interact physically with objects or devices required for therapy.

These considerations have implications for the design of delivery systems. At this stage of the patient journey, devices should be easy to learn, which may mean minimizing the number of steps required for use. Such a design should provide feedback for how the device works, and help assure the patient that the medicine has been delivered. Since this stage requires learning to use the device, clinicians should be able to demonstrate use easily and educate the patient on proper technique. Since the experience is still new, device interactions should not require patients to perform precise physical actuations or rely on finely tuned motor skills and sensory acuity. For example, using an insulin pen should not require precise orientation and alignment between the disposable needle and pen, as the diabetic patient likely may suffer trembling in the hands and have difficulty seeing small alignment details on system components. Rather, these components should be designed to guide the connection of discrete parts using simple motor interactions so they self-align and securely connect with minimal physical effort.

Early Treatment and Acclimation
As patients adapt to new routines and habits, they build experience. However, during this phase, treatment is not yet automatic. Steps may be forgotten, causing confusion for the patient when interacting with the device. Device developers should be aware of the possibility that patients will be acclimating to more than one prescription therapy, which can increase the difficulty of learning new routines and the risk that patients might confuse the steps and dosing frequencies associated with different medicines.

Maintaining a simple routine is easier on the patient, so use steps should be minimized at this stage. The system should provide clear and unambiguous feedback regarding the state of the device, and should confirm that patients have successfully performed the appropriate interactions to receive a proper dose. Such feedback and simplicity will help build habits that will facilitate ease of use down the line. For example, a dry powder inhaler system should be designed to indicate and differentiate discrete states, such as:

• Secured for transport/storage (e.g. the device is closed and sealed)
• Ready for preparing a dose (e.g. the device is open and ready for a dose to be advanced)
• Loaded and ready to deliver (e.g. the dose is ready to inhale)
• Successful delivery and readiness to be secured for transport/storage (e.g. the dosing chamber is empty, confirmation that the dose has been delivered)

At this point, ambiguity relative to any of these steps can compromise the integrity of the solution and introduce the risk of harm for the patient. Accidental discharges may be caused by uncertainty around whether or not a dose is loaded and ready for delivery. If a patient is not certain that a proper dose was delivered, he or she may administer a double dose. Complicated routines where medication must be extracted, measured accurately, transferred to a delivery device and then loaded/primed, greatly increase the potential for error, waste and misuse. This is particularly true before patients have performed these routines to the point where they become natural and habitual.

Getting Comfortable
As time passes and therapy regimens become more established, patients often start to feel better, may be less symptomatic and have come to terms with their disease state. This stage represents a very significant shift in how patients may consider their disease state and the relationship they have with a delivery system. The idea that they can “escape” the burden of suffering from disease may arise, and aspects of device use that may have been heavily appreciated during earlier stages, such as ease of learning and demonstrability, will likely have waned in importance.

At this stage, convenience of use and the impact that the therapies have on lifestyle and quality of life rise in importance. Devices that are quick and efficient to use, especially regarding the time required to prepare and actuate delivery, stand a better chance of encouraging adherent behavior. To avoid feelings of stigmatization, devices should be discreet. Such a device can provide a range of options for integrating the dosing regimen into daily life without calling undue attention to the device or patient. If a delivery system is inconvenient or overly conspicuous, it may negatively affect a patient’s emotional attitude, and thus the motivation to sustain adherent behavior.

Patient Lives a Better Life/Lapse in Therapy
Once disease management has become a permanent fixture in the lives of patients, emotional attitudes can develop that create a sense of complacency. Such an attitude can undermine adherence to a prescription regimen. For some disease sufferers, therapy may serve only to stabilize symptoms without eradicating them. Over time, these patients can become despondent about their condition and begin to doubt the effectiveness of their medication. Others may return to a near approximation of their lifestyle before diagnosis. Feeling “free” from the disease may embolden them to skip doses or lapse in their therapy entirely.

In these situations, lack of information regarding the benefits, value and effects of medical therapy can become a contributing factor to a lapse in adherence. A well-designed delivery system can become a platform to help monitor disease state progression. Devices designed with enabling technologies can then support the collection of information regarding physiologic measures, use patterns, adherence and other relevant aspects of disease management. Accordingly, this can serve to provide clinicians with more actionable information and lead to elevated standards of care. For patients, it can provide tangible means of how their prescription therapy is providing benefits and further incentivize adherent behavior.

While there are many methods available to test usability and reduce user-based risk, understanding the patient journey helps to combine not only the technical aspects of user interface with a device, but also the environments, emotions, needs and desires of the user at different stages of disease management. The ability to operate a device successfully depends on many characteristics, including the patients’ mental and emotional state, and knowledge of and experience with a particular device. Those characteristics change over time, and human factors experts can help pharma manufacturers design a device that will not only meet those needs while ensuring that the device is safe and effective, but also that it is used consistently within the guidelines of treatment at any point during the patient journey.

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Chris Evans is director of Innovation, Pharmaceutical Delivery Systems at West Pharmaceutical Services, Inc. He can be reached at [email protected]. The author would like to thank Ed Geiselhart, Director of Product Development & Planning, Insight Product Development, LLC, for his contribution to this article.