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Objective: To investigate whether head-worn displays (HWDs) help mobile participants make better alarm management decisions and achieve better situation awareness than alarms alone. Background: Patient alarms occur frequently in hospitals but often do not require clinical intervention. Clinicians may become desensitized to alarms and fail to respond to clinically relevant alarms. HWDs could make patient information continuously accessible, support situation awareness, and help clinicians prioritize alarms. Method: Experiment 1 ( n = 76) tested whether nonclinicians monitoring simulated patients benefited from vital sign information continuously displayed on an HWD while they performed a secondary calculation task. Experiment 2 ( n = 13) tested, across three separate experimental sessions, how effectively nursing trainees monitored simulated patients’ vital signs under three different display conditions while they assessed a simulated patient. Results: In Experiment 1, participants who had access to continuous patient information on an HWD responded to clinically important alarms 25.9% faster and were 6.7 times less likely to miss alarms compared to participants who only heard alarms. In Experiment 2, participants using an HWD answered situation awareness questions 18.9% more accurately overall than when they used alarms only. However, the effect was significant in only two of the three experimental sessions. Conclusion: HWDs may help users maintain continuous awareness of multiple remote processes without affecting their performance on ongoing tasks. Application: The outcomes may apply to contexts where access to continuous streams of information from remote locations is useful, such as patient monitoring or clinical supervision.

Bedside patient monitoring systems in hospitals are designed to monitor a patient’s physiology and to inform clinicians when a patient’s vital signs exceed normal boundaries by sounding an audible alarm. The alarms, however, are widely considered to be uninformative, and consistently unreliable which can lead to inappropriate alarm management and unintended patient decompensation. Several techniques to improve the alarm systems have been tested, ranging from user-centred approaches, like improved instructions for setting thresholds, to technological improvements, like “smart” alarm systems, but no universal solution to the problem has been adopted.Head-worn displays (HWDs) offer an alternative option: eliminating the problem by reducing reliance on bedside alarm systems entirely. Modern HWDs fit like pair of prescription glasses, but they contain a screen that could be used to display physiological information from a range of patients without the user having to physically interact with the device. Moreover, the patient information would be continuously accessible from anywhere, only requiring a rapid glance to the display, affording the user easy access to information that would otherwise be inaccessible. The HWD has the potential to reduce alarm mismanagement by creating an information rich environment, which is not possible with the current alarm systems.The results from previous research investigating HWDs have been mixed. On the one hand, studies have shown that the additional information can improve clinicians’ ability to monitor single patients for changes. On the other hand, HWDs can incur cognitive and perceptual challenges that can make the information on the display, and in the environment, less perceptible, which can worsen task performance. In addition, many current HWDs display information in the periphery, rather than over the forward field of view. What is still unknown, therefore, is how well peripheral stimuli on an HWD attract attention, and how effectively the device can be used in multiple patient contexts.This thesis reports a series of five experiments that were conducted to explore how information on an HWD guides attention towards unexpected events. Undergraduate students, both with and without clinical experience, were tested under a variety of conditions that investigated event detection and performance while they used an HWD versus when they had to rely on standard bedside monitors in a simulated hospital microworld.In Study 1 and Study 2, participants performed simple tasks in foveal vision and tried to detect abrupt changes to peripheral stimuli presented either on a computer monitor or on an HWD (Google Glass). The goal was to compare how abrupt changes in brightness and apparent motion affected detection rates for peripheral stimuli presented on the two displays. The results echoed those of previous HWD studies. Specifically, detection rates for stimuli on the HWD were significantly reduced, when compared to matched stimuli on a computer monitor, especially when presented further into the periphery. However, as the stimuli on the HWD increased in distinctiveness from their context, so did the rate of detection.In Study 3 and Study 4, participants monitored simulated patients in a computerised hospital microworld using either beside alarms alone, or bedside alarms plus a continuous stream of information presented either on a computer monitor or on an HWD (Google Glass). The goal was to explore whether the continuous stream of information improved participants’ ability to prioritise clinically relevant alarms (“sick patients”) over other alarms (“technological faults”). Additionally, in Study 4, I was interested in how performance on a cognitive task was affected while participants monitored their patients. Results indicated that the continuous displays significantly increased the number of relevant alarms that were managed, and reduced response times to the alarms, without affecting ongoing task performance.In Study 5, trained participants (second and third year nursing students) monitored simulated patients in three display conditions while completing a complex patient assessment task. The goal was to test participants’ ability to answer specific questions (situation awareness levels SA1 and SA2) about their patients when they were faced with either (a) alarms by themselves, (b) an HWD (Vuzix M100) and alarms, or (c) an HWD and a set of cycling auditory notifications. The results from the experiment suggested that the HWD can improve participants’ situation awareness, but only when combined with the cycling display, and only in the first session. Furthermore, the HWD was associated with better performance at the patient assessment task.Taken together, the findings suggest that HWDs have the potential to bring useful information to a clinician, allowing them to focus on the task at hand with less interruption. The additional information that the HWD provides may be useful for disambiguating alarms and maintaining continuous awareness of the status of multiple patients, which is not possible with the current design of bedside alarms. Appropriately designed HWDs may improve hospital ward environments by allowing clinicians to recognize negative trends sooner and to prioritise the management of sick patients over other tasks.

Head-worn displays have the potential to assist professionals in a wide variety of contexts by providing heads-up and hands-off information in real-time. For instance, nurses may be able to use head-worn displays to maintain peripheral awareness of the well-being of multiple patients while away from the nurses’ station and the patients’ beds. However, little is known about the advantages and disadvantages of head-worn displays in such contexts. In fact, many studies have shown that head-worn displays can lead to detriments in attention and visual performance. In three experiments, we tested people’s ability to detect simple, abrupt onset stimuli in peripheral vision when using a traditional computer monitor or Google Glass™. When using Google Glass, participants were significantly less likely to detect peripheral events. These data indicate that monocular optical see-through head-worn displays can make it harder to see peripheral stimuli. Stimuli need to be developed for head-worn displays that preserve their benefits for mobile users, while overcoming some of their disadvantages.

Objective To compare people's ability to detect peripherally presented stimuli on a monocular head-worn display (HWD) versus a conventional screen. Background Visual attention capture has been systematically investigated, but not with respect to HWDs. How stimulus properties affect attention capture is likely to be different on an HWD when compared to a traditional computer display. Method Participants performed an ongoing perceptual task and attempted to detect stimuli that were displayed peripherally on either a computer monitor or a monocular HWD. Results Participants were less able to detect peripheral stimuli when the stimuli were presented on a HWD than when presented on a computer monitor. Moreover, the disadvantage of the HWD was more pronounced when peripheral stimuli were less distinct and when the stimuli were presented further into the periphery. Conclusion Presenting stimuli on a monocular head-worn display reduces participants' ability to notice peripheral visual stimuli compared to presentation on a normal computer monitor. This effect increases as stimuli are presented further in the periphery, but can be ameliorated to a degree by using high-contrast stimuli. Application The findings are useful for designers creating visual stimuli intended to capture attention when viewed on a peripherally positioned monocular head-worn display.

Patient alarms occur frequently in hospitals, but they often do not require clinical intervention. As a result, clinicians can become desensitized to alarms and may fail to respond to them, including to alarms that are clinically relevant. Clinicians and researchers have investigated ways to make alarms more informative by adding delays (Gorges, Markewitz, & Westenskow, 2009) and developing ‘smart’ alarm systems (Imhoff, Kuhls, Gather, & Fried, 2009), but no approach has been universally accepted (for a review see Graham & Cvach, 2010). We are investigating the potential for head-worn displays (HWDs) to help mobile clinicians remotely monitor multiple patients while they perform other clinical tasks. We developed a computerized, multiple-patient monitoring microworld, and designed an initial study to test the efficacy of continuous displays for patient monitoring when added to conventional alarms. Specifically, the study tested whether continuous patient information, displayed on a conventional monitor, reduces patient waiting time for treatment and helps participants prioritize clinically relevant alarms over clinically irrelevant alarms. Clinically relevant alarms occurred when numerical values for heart rate, blood pressure or oxygen saturation becoming too high or too low. Clinically irrelevant alarms took the form of impossibly high or low values for any of the three vital signs, representing a signal failure. Participants navigated between patient rooms in the microworld using the keyboard and they responded to patient alarms using mouse clicks. The data showed that the total accumulated time in the 30-minute scenario that patients with a clinically relevant alarm were left waiting was significantly shorter in the alarms plus monitor condition (M = 11.6 min, SD = 4.0) than in the alarms only condition (M = 15.9 min, SD = 1.7); t(22) = 3.41, p = .001; d = 1.39. Participants in the alarms plus monitor condition relied less on the nursing aide to treat patient alarms (M = 6.25 alarms, SD = 6.70) than did participants in the alarms only condition (M = 11.5 alarms, SD = 4.36); t(22) = 2.27, p = .02; d = .93. We surmise that participants who had access to the continuous patient information could anticipate patient deteriorations and could distinguish clinically relevant versus irrelevant alarms without having to move to the patient’s bedside. Note that the difference between conditions was found without requiring participants to perform a secondary task. Although the present study is highly simplified, it demonstrates that situations can be set up in the microworld that show the advantage of having a continuous display of patient vital signs. We are currently testing whether the above results hold when continuous patient information is presented on a HWD and the participant is distracted by an ongoing task. Outcomes of the program of research will help determine whether or not head-worn displays could help clinicians monitor the status of multiple patients, while also potentially improving their ability to carry out other clinical tasks.