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The extent to which the relationships that are revealed between design features and behavior will improve patient safety, if generalized to labeling and packaging of medicines, is considered, by reviewing research evidence in other fields like food and pesticide. While the effects of the design variables on medication errors largely remain to be quantified, an organizing framework is provided to focus research efforts in this direction.

There are many reported problems with auditory warnings in critical care areas of hospitals such as the intensive care unit (ICU) and operating room. There are too many alarms; many of them are unnecessarily loud and continuous, which can be irritating and annoying for staff. The problem of excessive alarms is further complicated by the fact that there are no standards agreed between manufacturers on the auditory warnings used for medical equipment. Therefore, the same piece of equipment manufactured by different companies will have different alarms that could result in confusion. Another possibility as to why confusion could occur is because alarms are often inappropriate in terms of their 'urgency mapping.' This means there is generally no relationship between the urgency of a medical situation and the perceived urgency of the alarm that signals that condition. A further problem involves the number of false alarms that occur; that is, alarms that are not signalling a medical emergency. The following paper discusses these problems and suggests attempts to remedy some of them. There is also a brief discussion of the amount of monitoring that occurs on the ICU as the more monitors there are the greater the number of alarms there will be. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the effects of individual sound parameters on perceived (psychoacoustic) urgency. Experimental Series 1 showed that fundamental frequency, harmonic series, amplitude envelope shape, and delayed harmonics all have clear and consistent effects on perceived urgency. Experimental Series 2 showed that temporal and melodic parameters such as speed, rhythm, pitch range, and melodic structure also have clear and consistent effects on perceived urgency. The final experiment tested a set of 13 auditory warnings generated by an application of the earlier experimental findings. The urgency rank ordering of this warning set was predicted, and the correlation between the predicted and the obtained order was highly significant. The results of these experiments have a widespread application in the improvement of existing auditory warning systems and the design of new systems, where the psychoacoustic and psychological appropriateness of warnings could be enhanced. [ABSTRACT FROM AUTHOR]

It is well established that warning implementation should aim to achieve urgency mapping between the perceived urgency of the warning itself and the situational urgency of the condition that it indicates. This paper describes how Stevens Power Law [Psychological Review, 64, 153 181, 1957], which quantifies the relationship between objective parameters (such as the pitch of a warning) and subjective parameters (such as perceived urgency), can be applied to the design of auditory warnings to facilitate such urgency mapping. Studies that have quantified and predicted the effects of different warning parameters on perceived urgency using an application of Stevens Power Law are reported. [ABSTRACT FROM AUTHOR]

This paper describes the study of auditory affordances in the intensive treatment unit (ITU). The study compared representative sounds with traditional auditory warnings. Recognition performance for both the new and old warnings was compared. Recognition performance of the ITU staff was worse with the new set than with the old set of warnings, whereas the reverse was found with non-ITU staff. This suggests that although previous experience of the alarms aid recognition, there might be other more intuitive sounds which could be used on the ITU. [ABSTRACT FROM AUTHOR]

OCCUPATIONAL APPLICATIONSAuditory alarm signals are a safety measure that would benefit from improvement across many industries. There is a considerable research base that can be applied to the development and testing of audible alarms, though this is rarely done in practice. We describe a process that can be adopted in any area where audible alarm signals are widespread. A comprehensive approach to updating and improving auditory alarms requires consideration not only of individual alarm sounds but also of how the alarm signals will work together. We show the development and design of alarm signal sets following best practices from acoustic, psychoacoustic, and psychological knowledge to ensure that the resultant alarms are localizable, audible, easy to learn, appropriately urgency-mapped, and differentiable. We also describe benchmarking tests, and a protocol for thinking about how auditory alarm signals might be implemented in control rooms of different sizes.

In hospitals, clinicians are presented with varied and disorganized alarm sounds from disparate devices. While there has been attention to reducing inactionable alarms to address alarm overload, little effort has focused on organizing, simplifying, or improving the informativeness of alarms. We sought to elicit nurses' tacit interpretation of alarm events to create an organizational structure to inform the design of advanced alarm sounds or integrated alert systems. We used open card sorting to evaluate nurses' perception of the relatedness of different alarm events. Seventy hospital nurses sorted 89 alarm events into groups they believed could or should be indicated by the same sound. We conducted factor analysis on a similarity matrix of frequency of alarm event pairings to interpret how strongly alarm events loaded on different alarm groups (factors). We interpreted participants' grouping rationale from their group labels and comments. Urgency of response was the most common grouping rationale. Participants also grouped: 1) monitoring-related events, 2) device-related events, and 3) events related to calls and patients. Our findings support standardization and integration of alarm sounds across devices toward a simpler and more informative hospital alarm environment.

Given the ease with which the diverse array of environmental sounds can be understood, the difficulties encountered in using auditory alarm signals on medical devices are surprising. In two experiments, with nonclinical participants, alarm sets which relied on similarities to environmental sounds (concrete alarms, such as a heartbeat sound to indicate "check cardiovascular function") were compared to alarms using abstract tones to represent functions on medical devices. The extent to which alarms were acoustically diverse was also examined: alarm sets were either acoustically different or acoustically similar within each set. In Experiment 1, concrete alarm sets, which were also acoustically different, were learned more quickly than abstract alarms which were acoustically similar. Importantly, the abstract similar alarms were devised using guidelines from the current global medical device standard (International Electrotechnical Commission 60601-1-8, 2012). Experiment 2 replicated these findings. In addition, eye tracking data showed that participants were most likely to fixate first on the correct medical devices in an operating theater scene when presented with concrete acoustically different alarms using real world sounds. A new set of alarms which are related to environmental sounds and differ acoustically have therefore been proposed as a replacement for the current medical device standard. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Objectives: Accurate and timely identification of existing audible medical alarms is not adequate in clinical settings. New alarms that are easily heard, quickly identifiable, and discernable from one another are indicated. The "auditory icons" (brief sounds that serve as metaphors for the events they represent) have been proposed as a replacement to the current international standard. The objective was to identify the best performing icons based on audibility and performance in a simulated clinical environment., Design: Three sets of icon alarms were designed using empirical methods. Subjects participated in a series of clinical simulation experiments that examined the audibility, identification accuracy, and response time of each of these icon alarms. A statistical model that combined the outcomes was used to rank the alarms in overall efficacy. We constructed the "best" and "worst" performing sets based on this ranking and prospectively validated these sets in a subsequent experiment with a new subject sample., Setting: Experiments were conducted in simulated ICU settings at the University of Miami., Subjects: Medical trainees were recruited from a convenience sample of nursing students and anesthesia residents at the institution., Interventions: In Experiment 1 (formative testing), subjects were exposed to one of the three sets of alarms; identical setting and instruments were used throughout. In Experiment 2 (summative testing), subjects were exposed to one of the two sets of alarms, assembled from the best and worst performing alarms from Experiment 1., Measurements and Main Results: For each alarm, we determined the minimum sound level to reach audibility threshold in the presence of background clinical noise, identification accuracy (percentage), and response time (seconds). We enrolled 123 medical trainees and professionals for participation (78 with < 6 yr of training). We identified the best performing icon alarms for each category, which matched or exceeded the other candidate alarms in identification accuracy and response time., Conclusions: We propose a set of eight auditory icon alarms that were selected through formative testing and validated through summative testing for adoption by relevant regulatory bodies and medical device manufacturers.

Very little is known about people's ability to localize sound under varying workload conditions, though it would be expected that increasing workload should degrade performance. A set of eight auditory clinical alarms already known to have relatively high localizability (the ease with which their location is identified) when tested alone were tested in six conditions where workload was varied. Participants were required to indicate the location of a series of alarms emanating at random from one of eight speaker locations. Additionally, they were asked to read, carry out mental arithmetic tasks, be exposed to typical ICU noise, or carry out either the reading task or the mental arithmetic task in ICU noise. Performance in the localizability task was best in the control condition (no secondary task) and worst in those tasks which involved both a secondary task and noise. The data does therefore demonstrate the typical pattern of increasing workload affecting a primary task in an area where there is little data. In addition, the data demonstrates that performance in the control condition results in a missed alarm on one in ten occurrences, whereas performance in the heaviest workload conditions results in a missed alarm on every fourth occurrence. This finding has implications for the understanding of both 'inattentional deafness' and 'alarm fatigue' in clinical environments., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Background: Non-technical skills (NTS) have gained increasing recognition in recent years for their role in safe, effective team performance in healthcare. Gastrointestinal endoscopy is a procedure-based specialty with rapidly advancing technology, significant operational pressures and rapidly changing 'teams of experts'. However, to date there has been little focus on the effect of NTS in this field., Objectives: This review aims to examine the existing literature on NTS in gastrointestinal endoscopy and identify areas for further research., Method: A systematic search of MEDLINE, Embase, Cochrane Library, PsychINFO, CINAHL Plus and PubMed databases was performed using search terms Non-Technical Skills, Team Performance or Team Skills, and Endoscopy, Colonoscopy, OGD, Gastroscopy, Endoscopic Retrograde Cholangio-Pancreatography or Endoscopic Ultrasound., Results: Eighteen relevant publications were found. NTS are deemed an essential component of practice, but so far there is little evidence of their integration into training or competency assessment. Those studies examining the effects of NTS and team training in endoscopy are small and have variable outcome measures with limited evidence of improvement in skills or clinical outcomes. NTS assessment in endoscopy is in its early phases with a few tools in development., Conclusions: The current literature on NTS in gastrointestinal endoscopy is limited. NTS, however, are deemed an essential component of practice, with potential positive effects on team performance and clinical outcomes. A validated reliable tool would enable evaluation of training and investigation into the effects of NTS on outcomes. There is a clear need for further research in this field., Competing Interests: Competing interests: None declared.

Objective Four sets of eight audible alarms matching the functions specified in IEC 60601-1-8 were designed using known principles from auditory cognition with the intention that they would be more recognizable and localizable than those currently specified in the standard. Background The audible alarms associated with IEC 60601-1-8, a global medical device standard, are known to be difficult to learn and retain, and there have been many calls to update them. There are known principles of design and cognition that might form the basis of more readily recognizable alarms. There is also scope for improvement in the localizability of the existing alarms. Method Four alternative sets of alarms matched to the functions specified in IEC 60601-1-8 were tested for recognizability and localizability and compared with the alarms currently specified in the standard. Results With a single exception, all prototype sets of alarms outperformed the current IEC set on both recognizability and localizability. Within the prototype sets, auditory icons were the most easily recognized, but the other sets, using word rhythms and simple acoustic metaphors, were also more easily recognized than the current alarms. With the exception of one set, all prototype sets were also easier to localize. Conclusion Known auditory cognition and perception principles were successfully applied to an existing audible alarm problem. Application This work constitutes the first (benchmarking) phase of replacing the alarms currently specified in the standard. The design principles used for each set demonstrate the relative ease with which different alarm types can be recognized and localized.

The failure of humans to respond to auditory medical alarms has resulted in numerous patient injuries and deaths and is thus a major safety concern. A relatively understudied source of response failures has to do with simultaneous masking, a condition where concurrent sounds interact in ways that make one or more of them imperceptible due to physical limitations of human perception. This paper presents a method, which builds on a previous implementation, that uses a novel combination of psychophysical modeling and formal verification with model checking to detect masking in a modeled configuration of medical alarms. Specifically, the new method discussed here improves the original method by adding the ability to detect additive masking while concurrently improving method usability and scalability. This paper describes how these additions to our method were realized. It then demonstrates the scalability and detection improvements via three different case studies. Results and future research are discussed., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This study compared the ability of forty anaesthetists to judge absolute levels of oxygen saturation, direction of change, and size of change in saturation using auditory pitch and pitch difference in two laboratory-based studies that compared a linear pitch scale with a logarithmic scale. In the former the differences in saturation become perceptually closer as the oxygenation level becomes higher whereas in the latter the pitch differences are perceptually equivalent across the whole range of values. The results show that anaesthetist participants produce significantly more accurate judgements of both absolute oxygenation values and size of oxygenation level difference when a logarithmic, rather than a linear, scale is used. The line of best fit for the logarithmic function was also closer to x = y than for the linear function. The results of these studies can inform the development and standardisation of pulse oximetry tones in order to improve patient safety., (Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.)