62366 and IEC 60601-1-6 have been developed and are used during the design process of single medical devices. When thinking of compatibility in multiplicity ...
Compatibility in multiplicity: towards a complex understanding of medical devices use Karen Lange Morales Institute of Ergonomics, Darmstadt University of Technology MIMAPRO Research Group, Universidad Nacional de Colombia Sinja Röbig Institute of Ergonomics, Darmstadt University of Technology Ralph Bruder Institute of Ergonomics, Darmstadt University of Technology
ABSTRACT This paper introduces the concept of compatibility in multiplicity as a leading thread for tackling the use of multiple medical devices in concrete settings. It is part of a broader research project aiming at recognizing the use of medical devices from a complex perspective. The concept is tackled from usability/ergonomics and Actor Network Theory (ANT) and Post-ANT approaches. It goes beyond the standard view of technology (technological determinism), understanding the use of medical devices as multiple sociomaterial practices. This effort looks for contributing to improve medical devices design, procurement and incorporation by outlining the implications of compatibility complexity.
INTRODUCTION The World Health Organization recognizes medical devices as one health technology. However, a medical device, by itself, is not enough to be considered a health technology in a broader sense: it becomes part of a useful specific health technology when it is used, when a medical procedure is enacted, when it interacts appropriately with other actors like different medical devices, healthcare staff, patients, healthcare institution, providers, norms, etc. This “appropriate interaction” may be called compatibility, and a “non-appropriate interaction” may be called incompatibility. There is evidence of non-appropriate interactions or incompatibilities i.e. medical errors and adverse events related with medical devices use, leading to serious consequences in procedures performance, affecting patient’s and healthcare staff’s health and safety In order to improve compatibility, and from the standard view of technology, two assumptions underlie current usability and ergonomics research and development of medical devices: first, that it is possible to predict incompatibilities between medical devices and users or systems; second, as incompatibilities can be predicted, it is possible to avoid them through control mechanisms like guidelines, norms and standards, applied along design and production, procurement and incorporation, and availability (including use) stages. This approach is leading to an improvement of the compatibility between independent medical devices and users, but it is necessary to look beyond isolated relationships, and understand compatibility in the performance of a specific medical procedure emerging technology. Actors’ compatibility in a medical procedure Authors’ copy – previous to publication – Lange Morales, K., Röbig, S., Bruder, R. – Compatibility in multiplicity: Towards a complex understanding of medical devices use. Published in Book: Healthcare systems ergonomics and patient safety 2011, Edition: 1. P ublisher: Taylor & Francis Group, Editors: Sara Albolino, Sebastiano Bagnara, To mmaso Bellandi, Javier Llaneza, Gustavo Rosal, Riccardo Tartaglia, pp.334-337.
performance is far more complex than usability of a specific medical device. That is why the concept of compatibility in multiplicity is introduced, referred to an appropriate interaction of all actors (or the most of them) enacting related medical procedures. One way of dealing with complexity beyond technological determinism is tackling compatibility in multiplicity from Actor Network Theory (ANT) and Post-ANT perspectives. Aiming at outlining the possibilities and limits of the proposed concept, this paper offers a preliminary approach to the question: How can compatibility in multiplicity be understood from usability, ergonomics and ANT/Post-ANT viewpoints?
COMPATIBILITY IN MULTIPLICITY: THE USABILITY PERSPECTIVE Usability is generally defined as the “extent to which a system, product or service can be used by specified users to achieve specified goals with effectiveness, efficiency and satisfaction in a specified context of use” [1]. Therefore, the interaction with medical devices can be called “appropriate” if it is efficient, effective and to the satisfaction of the user. Since usability is of a high importance for medical devices, standards to support a usable design for medical devices, e.g. ANSI/AAMI HE74, IEC 62366 and IEC 60601-1-6 have been developed and are used during the design process of single medical devices. When thinking of compatibility in multiplicity from the usability perspective it is not only meant that one kind of medical device, e.g. an anaesthesia machine, can be used by the user with effectiveness, efficiency and satisfaction, but that the user can interact with effectiveness, efficiency and satisfaction with a combination of devices simultaneously or during the same process. This shift leads to the question...which components do have an effect on the usability of a combination of medical devices? For example, it is expected that the architecture of a product has an influence on the usability. Displays location should always be the same; the menu structures should always follow the same rules, etc. Considering compatibility in multiplicity from the usability perspective means not only that one kind of medical device, e.g. an anaesthesia machine, is always designed in a similar way to reduce the effort of learning to interact with a new anaesthesia machine every time new devices are bought or the staff works in another operation room with different equipment. It is also meant to design different kinds of medical devices in a similar way to have the same handling logic behind different medical devices. The idea behind this is to reduce the time needed for training the medical staff on different devices and to reduce the operation time and reduce the number of mistakes happening when interacting with medical devices since the medical staff does not have to rethink every time when using a different device. Performing a usability study of a combination of medical devices is more complex than a usability study of one device, or only a couple of functions of one device. Therefore it probably makes sense to not only observe the test but also to record the test to be able to analyze the details after performing the test. To be able to give advice on how to combine different medical devices it might also make sense to make a usability study of one medical device fist to get a “baseline”. Afterwards, different combinations Authors’ copy – previous to publication – Lange Morales, K., Röbig, S., Bruder, R. – Compatibility in multiplicity: Towards a complex understanding of medical devices use. Published in Book: Healthcare systems ergonomics and patient safety 2011, Edition: 1. P ublisher: Taylor & Francis Group, Editors: Sara Albolino, Sebastiano Bagnara, To mmaso Bellandi, Javier Llaneza, Gustavo Rosal, Riccardo Tartaglia, pp.334-337.
of medical devices can be tested and compared, and results will show which combinations are better from the usability perspective. The results might also give a hint why some combinations are better than others.
COMPATIBILITY IN MULTIPLICITY: THE ERGONOMICS PERSPECTIVE Ergonomics is defined as “the scientific discipline concerned with the understanding of interactions among humans and other elements of a system, and the profession that applies theory, principles, data and methods to design in order to optimize human well-being and overall system performance” [2]. In line with this, the idea of compatibility as an “appropriate interaction” among humans and other elements of a system is a core concept in ergonomics, although it has been generally expressed in an unstructured way by using the term “fit” [3]. In order to overcome the uncertainty and lack of structure of the concept, Karwowski proposes a corroborative science to ergonomics called symvatology, with the final goal of developing a universal measure of compatibility for design, testing and evaluation of ergonomic systems [3]. To have “appropriate interactions” among humans and other elements of a system is the reason for the existence of ergonomics. Along the historical development of ergonomics, many levels of analysis have been added. Considering ergonomics as the Human-system interface technology, Hendrick proposes five major components: hardware ergonomics, environmental ergonomics, cognitive ergonomics, job design ergonomics, and macroergonomics. The first four components constitute what is called microergonomics [4]. From this viewpoint, ‘compatibility’ and ‘compatibility in multiplicity’ can be associated with different levels, i.e. micro and macroergonomics. Compatibility (or “appropriate interaction”) refers to the extent to which elements of a system (medical devices, users and physical spaces) can interact without affecting themselves or the system’s purpose negatively, associated with microergonomics; and it can be said that there is compatibility in multiplicity when a work system (structure and related processes) supports an appropriate interaction of the personnel subsystem and the technological subsystem, including its relationship with external environment characteristics.
COMPATIBILITY IN MULTIPLICITY: THE ANT / POST-ANT PERSPECTIVE One way of dealing with complexity involved in MDs use, beyond the standard conception of technology, are Actor Network Theory (ANT) and Post-ANT approaches, as ANT’s departure point is a view of the world as multiple and complex [5]. ANT is an alternative constructivist social theory, developed first by Bruno Latour, Michael Callon and John Law in the early 80s. Post-ANT is the given name for contributions made by scholars like Annemarie Mol, the same John Law and many other authors, that even sharing basic concepts of ANT, developed other postulates that enhance, discuss, or modify ANT’s original scope. A more technical description of ANT refers to it as a “material semiotic” method, where simultaneously material (things) and semiotic (concepts) relations are mapped. Authors’ copy – previous to publication – Lange Morales, K., Röbig, S., Bruder, R. – Compatibility in multiplicity: Towards a complex understanding of medical devices use. Published in Book: Healthcare systems ergonomics and patient safety 2011, Edition: 1. P ublisher: Taylor & Francis Group, Editors: Sara Albolino, Sebastiano Bagnara, To mmaso Bellandi, Javier Llaneza, Gustavo Rosal, Riccardo Tartaglia, pp.334-337.
One of ANT’s basic statements is that society and technology cannot be cut and separate. In other words, society is not made by human relations, and techniques are not made by non- human relations [6]. This way the dualism society/technology disappears. Practices are seen as a continuous making and re- making, where actors and declarations change, come and go. It is a symmetric, dynamic and unfinished way of understanding sociomaterial practices. Compatibility is a foreign concept for ANT/Post-ANT. However, it can be understood as the extent to which actors (medical devices, patient, healthcare staff, norms, etc) are enrolled in a programme of action (performance of a medical procedure), in order to fulfil a declaration (repair a broken leg). There is an appropriate interaction between actors (human / non- human), when controversies (tensions, “mismatch”) between them are overcome. The concept of compatibility in multiplicity is driven from the proposal of Annemarie Mol [7]. She proposes to put practices in the foreground, rather than focusing on different people’s perspectives, understanding objects as things that are manipulated in practices. As practices are done differently because the object of manipulation tends to differ, there is not just one reality: reality multiplies. In line with this, from ANT/Post-ANT viewpoint, it can be said that there is compatibility in multiplicity, when the performance or enactment of related practices of a medical procedure are successful.
CONCLUSIONS AND FUTURE WORK Each perspective introduced offers a different and complementary approach to what can be understood as compatibility, and compatibility in multiplicity. Figures 1 and 2 illustrate a preliminary idea of the possible scope of each viewpoint.
Figure 1. Scope of the concept of compatibility from usability, ergonomics and ANT/Post-Ant (Karen Lange Morales, 2011)
Authors’ copy – previous to publication – Lange Morales, K., Röbig, S., Bruder, R. – Compatibility in multiplicity: Towards a complex understanding of medical devices use. Published in Book: Healthcare systems ergonomics and patient safety 2011, Edition: 1. P ublisher: Taylor & Francis Group, Editors: Sara Albolino, Sebastiano Bagnara, To mmaso Bellandi, Javier Llaneza, Gustavo Rosal, Riccardo Tartaglia, pp.334-337.
Figure 2. Scope of the concept of compatibility in multiplicity from usability, ergonomics and ANT/Post-Ant (Karen Lange Morales, 2011) Usability and microergonomics need to bracket practices, in order to reduce complexity. Macroergonomics deals with higher levels and therefore addresses more complex issues. However, just like usability and microergonomics, it establishes categories a priori, making distinctions between human and non- human actors, and this way the dualism society/technology is present. To be able to tackle compatibility in multiplicity of combination of medical devices or multiple sociomaterial practices, some further research is needed. For example, it has to be clarified which components of medical devices are influencing the usability in the first step. In the second step concrete hints for manufacturers can be generated which support them in creating those components in a similar way for different devices to improve the usability of whole medical device families.
REFERENCES [1] ISO 9241-210:2010 - Ergonomics of human-system interaction -- Part 210: Humancentred design for interactive systems. [2] IEA (2000) What is ergonomics. http://www.iea.cc/01_what/What%20is%20Ergonomics.html [3] Karwowski, Waldermar (2000) Symvatology: the science of an artifact- human compatibility. Theor. Issues in Ergon. Sci. (1) 1. 76-91. [4] Hendrick, Hall W. (2000) The technology of ergonomics. Theor. Issues in Ergon. Sci. (1) 1. 22-33. [5] Gad C, Bruun Jensen C. (2010) On the consequences of post-ANT. Science, Technology & Human Values;35(1):55. Authors’ copy – previous to publication – Lange Morales, K., Röbig, S., Bruder, R. – Compatibility in multiplicity: Towards a complex understanding of medical devices use. Published in Book: Healthcare systems ergonomics and patient safety 2011, Edition: 1. P ublisher: Taylor & Francis Group, Editors: Sara Albolino, Sebastiano Bagnara, To mmaso Bellandi, Javier Llaneza, Gustavo Rosal, Riccardo Tartaglia, pp.334-337.
[6] Latour, Bruno (1992) Where are the missing masses? The sociology of a few mundane artifacts. Shaping technology/building society: Studies in sociotechnical change. 225-258. [7] Mol A. (2002). The body multiple: Duke Univ. Press.
Authors’ copy – previous to publication – Lange Morales, K., Röbig, S., Bruder, R. – Compatibility in multiplicity: Towards a complex understanding of medical devices use. Published in Book: Healthcare systems ergonomics and patient safety 2011, Edition: 1. P ublisher: Taylor & Francis Group, Editors: Sara Albolino, Sebastiano Bagnara, To mmaso Bellandi, Javier Llaneza, Gustavo Rosal, Riccardo Tartaglia, pp.334-337.
