Usability and Human Factors: Human Factors and Healthcare
Audio Transcript
Slide 1: Human Factors and Health Care
This lecture provides an introduction to the discipline of human factors with a particular focus on human factors concepts and principles. We will also characterize the ways in which human factors analysis makes use of concepts from applied cognitive psychology. We will particularly focus on the issue of selective and divided attention. The subsequent section of this unit focuses on patient safety issues and concepts as well as an introduction to the analysis of human error. The focus is on understanding the nature of human error and appreciating a systems-centered approach, which emphasizes the multiplicity and complexity of causes of human error.We then turn our attention to workload, which is an important construct pertaining to the potential for error in a work setting. In the final section of this unit, we will examine medical devices and discuss 2 human factor studies that examine efficacy of such devices in clinical and home-health contexts.
Slide 2: Unit Objectives
This unit covers the following objectives:
1. Distinguish between human factors and human computer interactions (HCI) as they apply to usability
2. Explain how cognitive, physical and organization ergonomics can be applied to human factors engineering and
3. Describe how the concepts of mental workload, selective attention and information overload affect usability
Slide 3: Human Factors & Health Care
Human factors is a discipline devoted to the study of technological systems and how people work with them or are affected by them. It is concerned with the full range of health-related technologies and systems used by a diverse range of people including clinicians, hospital administrators, health consumers and patients.
Slide 4: Human Factors and HCI Redux: Differences
In this course, we will frequently talk about both human factors and human computer interaction (HCI). They are different disciplines with different histories and separate professional and academic societies. HCI is more focused on computing and cutting-edge design and technology. Human factors (HF) focus on a range of systems that covers a wider range of hospital and other technologies.Patient safety is one of the central issues in human factors research.
Slide 5: Human Factors and HCI Redux: Similarities
However, the 2 domains employ many of the same methods of evaluation and both strongly emphasize a user-centered approach to design and a systems-centered approach to the study of technology use. Researchers and professionals in both domains draw on the same set of theories including cognitive engineering.
Slide 6: History of Human Factors
This slide covers the history of human factors from the earliest efforts of engineers to increase the productivity of factor workers by changing environmental conditions. The discipline became formalized towards the end of World War II and shortly thereafter began an age of great expansion. This time corresponded to the beginning of the space age and the rapid growth of the automobile industry as well as aviation. The last 20-30 years have witnessed a considerable growth of the discipline in scope and importance. Health care has also become a focal point of work in Human Factors.
Slide 7: Why is Human Factors Increasingly Important
Human factors have grown in importance and in public awareness in recent decades. Some of this is due to an increase in the use of technology by a diverse population of users (most of whom are not experts), a growing awareness of safety, and the cost of error. In industry, there is an increasing recognition of the need for better quality control and the fact that it conveys a competitive edge. The car industry is a case in point. There is a general perception that Japanese and European cars are of greater quality and this has hurt the sales of North American cars.
Slide 8: Human Factors Objective
What is the central focus of HF work? Broadly, it is people and their interaction with the gamut of technologies and systems. The goal of this work is to optimize these technologies such that they match the capabilities and limitations of people who use them. As we will discuss, cognitive psychology plays a very important role in human factors analysis.
Slide 9: Examples of Application Areas
These are just some examples of application areas in human factors. We will focus on computer systems and patient safety, but we will also touch on other areas of interest that exemplify important concepts and principles.
Slide 10: Nuclear Power Plant Control Room
Here is a picture of a control room in a nuclear power plant. Safety is a crucial issue in these settings. Homer Simpson is probably not the embodiment of the ideal nuclear power safety inspector, although he is the best known. The picture illustrates the immense complexity of such an environment and one can imagine the demands on human operators. There have been several significant accidents in such plants and they have served as excellent case studies in human factors engineering.
Slide 11: Airplane Cockpit
The aviation industry is one of the first to embrace the discipline of human factors as well as human factors engineering principles. Although airplane crashes make the front pages of our newspapers when they happen, the airline industry has an excellent safety record in recent decades. They have evolved a rather elaborate set of procedures for ensuring safe practices, which includes rigorous training of pilots and ensuring maintenance of pilot’s competencies. We hear about the failures in aviation, but on balance they set a high standard on matters of safety. In the last decade or so, the health care sector has to some extent patterned itself after the aviation industry. For example, checklists, structured communication techniques, error reporting and simulator training are some of ways in which the healthcare sector has endeavored to adopt the safety practices and methods of the aviation industry.
Slide 12: Human Factors in Medicine
These are some examples of applications of human factors work in medicine. Infusion pumps are used to infuse fluid and medications into patient’s circulatory system. In recent years, there have been growing concerns about the safety of these devices. Over one million patients are injured annually by medication errors. Although most are relatively minor, some result in serious patient harm and even fatalities.The effects of fatigue, night shift work, and sleep deprivation on human performance and the safety of medical care are subjects of enormous interest within the medical community. Although this remains a controversial issue, several states have mandated that medical residents limit the number of consecutive hours in a given shift. Infection control continues to be a serious problem in hospitals.Simple intervention like the close scrutiny of hand-washing behavior of clinicians has had a significant impact on controlling infection rates in hospitals. All technology has unintended consequences ranging from positive to highly detrimental to patient safety.
We will return to the issue of patient safety and discuss some of these examples after we review some of the core concepts and central issues in human factors.
Slide 13: Human Factors/Ergonomics
As we discussed previously, human factors is a profession that applies theory, principles, data, methods to design in order to optimize human well-being and overall system performance. Unlike HCI, a system does not merely refer to a computing system. It may be a device, person, team, organization, or policy to name a few.
Slide 14: Human Factors Ergonomics: 3 Major Domains
Ergonomics is broadly conceived as the study of work and factors that affect it. The term is sometimes used interchangeably with human factors. In any case, we can characterize 3 major domains.
Slide 15: Physical Ergonomics
Physical Ergonomics are concerned with physical activity and covers a wide range of related issues including understanding and reducing injuries in the workplace (such as repetitive stress injury).
Slide 16: Organizational Ergonomics
Organizational Ergonomics is concerned with the study of sociotechnical systems. The topics in this area include communication, teamwork, participatory design, and quality management. An example of an application to health is taking steps to reduce stress and employee burnout. Redesigning work schedules is one way to try and diminish the risk of burnout.
Slide 17: Cognitive Ergonomics
Cognitive Ergonomics addresses the gamut of cognitive issues including mental workload, an issue that we will come back to later in this lecture, and usability of systems, which is a central issue in this course. This lecture focuses predominantly on cognitive issues.
Slide 18: Human Factors & Applied Cognitive Psychology
Human factors can be construed as a discipline guided by principles of engineering and applied cognitive psychology. Human factors analysis applies knowledge about the strengths and limitations of humans to design interactive systems, equipment, and their environment. The objective is to ensure their effectiveness, safety, and ease of use. Mental models and issues of decision making are central to human factors analysis. Any system will be easier and less burdensome to use to the extent that that it is co-extensive with users’ mental models.
We will now focus on matters of attention, which is also a central concern in human factors analysis.
Slide 19: Human Attention
Human factors focus on different dimensions of cognitive capacity, including memory, attention, and workload. Our perceptual system inundates us with more stimuli than the cognitive system can possibly process. Attention mechanisms enable us to selectively prioritize and attend to certain stimuli and attenuate other ones. Attentional resources are limited. They also have the property of being sharable which enables us to multitask by dividing our attention between 2 activities.If we are driving on a highway, we can easily have a conversation with a passenger at the same time. However, as the skies get dark or the weather changes or suddenly you find yourself driving through winding mountainous roads, you will have to allocate more of your attentional resources to driving and less to the conversation. Most states have outlawed the use of handheld cell phones while driving because they serve to divide one’s attentional resources and greatly increase the likelihood of accidents and highway fatalities. On the basis of studies thus far, it is not clear that using a hands free cell phone has any effect on reducing driving accidents. It has the effect of sapping one’s needed attentional resources.
Slide 20: Selective Attention
We have the ability to ignore extraneous information and focus on relevant information. However, performance typically declines as the number of sources of information increases. Information overload is a common cause of performance errors.
Slide 21: Information Overload
This slide describes some of the conditions for overload. If you are under pressure to increase the pace of your performance or if you are burdened by a heavy information load, the quality or accuracy of performance is likely to degrade.There is a speed/accuracy tradeoff. As you increase your speed of performance, beyond a certain threshold, you increase the probability that the quality or accuracy of your work will degrade.
Slide 22: Selective Attention
This slide enumerates a number of factors that drive the selection of channels to attend. Events or stimuli that are salient tend to capture our attention. Loud music or a conversation where someone mentions your name is likely to capture your attention. We tend to sample the world where we expect to find information, and attend to channels based on how valuable it is to look or costly to miss. This can be a property of expertise. Nuclear power plant operators, Homer Simpson aside, or intensive care nurses are trained to attend to particular signals, which are vitally important. If we are inundated with stimuli, such efforts may be fruitless. For example, trying to study complex subject materials in a noisy café may be very effortful. On the other hand, we may be able to read a newspaper or a novel in the same environment.
Slide 23: Divided Attention or Time Sharing
Time-sharing refers to the ability to perform more than one cognitive task by attending to both at once or rapidly switching back and forth between them. We do that routinely divide our attention when working on our computer. We may be writing, listening to music and watching out for an important email.However, given the fact that cognitive resources for attention are relatively limited, time-sharing often results in a drop in performance for one or both tasks. We can modulate our attention resources by giving more attention to the task that is more important at the moment.
Slide 24: Human Factors Design Implications
On the basis of human factors research, we can draw the following design implications. If possible, reduce the number of channels that one needs to attend to. Make sources of information as distinct as possible. For example, an intensive care nurse may hear 10 or 12 different kinds of alarms that signal various kinds of patient needs or concerns. However, the sounds are sufficiently distinct that he or she will know which ones warrant immediate attention and which ones can wait a little longer. Electronic health records can be designed (or templates developed) that correspond better to the desired clinician workflow and displays can be structured to provide easier access to needed information. Work scheduling can be used to reduce fatigue and improve performance. Although training is not a substitute for poor design, it can provide workers with strategies and resources to work more productively within the limitations of a given system.
Slide 25: Summary
In summary, we considered the growing importance of human factors in health and other domains, briefly considered different domains of human factors and ergonomics. Applied cognitive psychology provides some of the theoretical basis for understanding human performance in the context of human factors. The lecture also considered the issue of attention and the important role it plays in modulating performance in the work place. In the next section, we consider the issue of patient safety and models of error.
Slide 26: References
No Audio
end
Health IT Workforce CurriculumUsability and Human Factors1
Version 3.0 / Spring 2012Human Factors and Healthcare
Unit 4a
This material (Comp15_Unit4a) was developed by Columbia University, funded by the Department of Health and Human Services, Office of the National Coordinator for Health Information Technology under Award Number 1U24OC000003.