Assessing Usability of Untethered Head-Mounted Displays for Medical Education: A Within-Person Randomized Trial.

INTRODUCTION: Recent meta-analyses have found immersive technology to be effective for training, yet there is limited research on user experience with head-mounted displays (HMDs) in the medical domain. If emerging immersive displays do not meet usability standards in the context of healthcare simulation, the technology may cause frustration or hinder learning outcomes. This is the first experimental comparison of usability in commercial untethered, "all-in-one" HMDs for healthcare simulation. METHODS: The usability and comfort of three commercial untethered HMDs (Oculus Go, Oculus Quest, and Lenovo Mirage Solo) were tested using a randomized within-person design such that each headset was evaluated by all participants in a random sequence. During the experiment, participants (n = 9) interacted with a simulated healthcare environment in each headset and then responded to usability and comfort surveys. RESULTS: All of the HMDs were rated as having higher than average usability compared with an industry benchmark scale, the System Usability Scale. Only one of the headsets had a usability rating in the highest range, which was significantly higher than the lowest rated headset ( P = 0.047, Cohen d = 0.901). In addition, feelings of discomfort with the headsets were low, and comfort ratings did not differ significantly between headsets ( P > 0.05). CONCLUSIONS: Untethered HMDs had acceptable user experience ratings during a healthcare simulation task, but some headsets were rated higher on usability. Because usability is important for learner engagement and training outcomes, educators should confirm that immersive displays meet usability standards before implementation.

Training detection of camouflaged targets in natural scenes: Backgrounds and targets both matter.

As target-background similarity increases, search performance declines, but this pattern can be attenuated with training. In the present study we (1) characterized training and transfer effects in visual search for camouflaged targets in naturalistic scenes, (2) evaluated whether transfer effects are preserved 3 months after training, (3) tested the suitability of the perceptual learning hypothesis (i.e., using learned scene statistics to aid camouflaged target detection) for explaining camouflage search improvements over training, and (4) provide guidance for camouflage detection training in practice. Participants were assigned to one of three training groups: adaptive camouflage (difficulty varied by performance), massed camouflage (difficulty increased over time), or an active control (no camouflage), and trained over 14 sessions. Additional sessions measured transfer (immediately post training) and retention of training benefits (10 days and 3 months post training). Both the adaptive and massed training groups showed improved camouflaged target detection up to 3 months following training, relative to the control. These benefits were observed only with backgrounds and targets that were similar to those experienced during training and are broadly consistent with the perceptual learning hypothesis. In practice, training interventions should utilize stimuli similar to the operational environment in which detection is expected to occur.

Factors associated with cytomegalovirus serostatus in young people in England: a cross-sectional study.

BACKGROUND: Human cytomegalovirus (CMV) is a common herpesvirus which is estimated to infect 83% of the global population. Whilst many infections are asymptomatic, it is an important cause of morbidity and mortality, particularly for immunocompromised people and for infants who are congenitally infected. A vaccine against CMV has been stated as a public health priority, but there are gaps in our understanding of CMV epidemiology. To guide potential future vaccination strategies, our aim was to examine risk factors for CMV seropositivity in young people in England. METHODS: The Health Survey for England (HSE) is an annual, cross-sectional representative survey of households in England during which data are collected through questionnaires, and blood samples are taken. We randomly selected individuals who participated in the HSE 2002, aiming for 25 participants of each sex in each single year age group from 11 to 24 years. Stored samples were tested for CMV antibodies. We undertook descriptive and regression analyses of CMV seroprevalence and risk factors for infection. RESULTS: Demographic data and serostatus were available for 732 individuals, of whom 175 (23.7%) were CMV-seropositive. CMV seroprevalence was associated with age, with 18.3% seropositive at 11-14 years compared to 28.3% at 22-24 years. CMV serostatus was also higher in people of non-white ethnicity (adjusted odds ratio [aOR] 6.22, 95% confidence interval [CI] 3.47-11.14), and in adults who were seropositive for EBV (aOR 2.08 [1.06-4.09]). There was no evidence that smoking status, occupation, body mass index and region of England were associated with CMV serostatus. CONCLUSIONS: CMV seroprevalence is strongly associated with ethnicity, and modestly increases with age in 11-24-year-olds. A greater understanding of the transmission dynamics of CMV, and the impact of this on CMV-associated morbidity and mortality, is necessary to inform effective vaccination strategies when a vaccine for CMV becomes available.

Which Phish Is on the Hook? Phishing Vulnerability for Older Versus Younger Adults.

OBJECTIVE: To determine if there are age-related differences in phishing vulnerability and if those differences exist under various task conditions (e.g., framing and time pressure). BACKGROUND: Previous research suggests that older adults may be a vulnerable population to phishing attacks. Most research exploring age differences has used limiting designs, including retrospective self-report measures and restricted email sets. METHOD: The present studies explored how older and younger adults classify a diverse sample of 100 legitimate and phishing emails. In Experiment 1, participants rated the emails as either spam or not spam. Experiment 2 explored how framing would alter the results when participants rated emails as safe or not safe. In Experiment 3, participants performed the same task as Experiment 1, but were put under time pressure. RESULTS: No age differences were observed in overall classification accuracy across the three experiments, rather all participants exhibited poor performance (20%-30% errors). Older adults took significantly longer to make classifications and were more liberal in classifying emails as spam or not safe. Time pressure seemed to remove this bias but did not influence overall accuracy. CONCLUSION: Older adults appear to be more cautious when classifying emails. However, being extra careful may come at the cost of classification speed and does not seem to improve accuracy. APPLICATION: Age demographics should be considered in the implementation of a cyber-training methodology. Younger adults may be less vigilant against cyber threats than initially predicted; older adults might be less prone to deception when given unlimited time to respond.

Predictors of Epstein-Barr virus serostatus in young people in England.

BACKGROUND: Epstein-Barr virus (EBV) is an important human pathogen which causes lifelong infection of > 90% people globally and is linked to infectious mononucleosis (arising from infection in the later teenage years) and several types of cancer. Vaccines against EBV are in development. In order to determine the most cost-effective public health strategy for vaccine deployment, setting-specific data on the age at EBV acquisition and risk factors for early infection are required. Such data are also important to inform mathematical models of EBV transmission that can determine the required target product profile of vaccine characteristics. We thus aimed to examine risk factors for EBV infection in young people in England, in order to improve our understanding of EBV epidemiology and guide future vaccination strategies. METHODS: The Health Survey for England (HSE) is an annual, cross-sectional representative survey of households in England during which data are collected via questionnaires and blood samples. We randomly selected individuals who participated in the HSE 2002, aiming for 25 participants of each sex in each single year age group from 11 to 24 years. Stored samples were tested for EBV and cytomegalovirus (CMV) antibodies. We undertook descriptive and regression analyses of EBV seroprevalence and risk factors for infection. RESULTS: Demographic data and serostatus were available for 732 individuals. EBV seroprevalence was strongly associated with age, increasing from 60.4% in 11-14 year olds throughout adolescence (68.6% in 15-18 year olds) and stabilising by early adulthood (93.0% in those aged 22-24 years). In univariable and multivariable logistic regression models, ethnicity was associated with serostatus (adjusted odds ratio for seropositivity among individuals of other ethnicity versus white individuals 2.33 [95% confidence interval 1.13-4.78]). Smoking was less strongly associated with EBV seropositivity. CONCLUSIONS: By the age of 11 years, EBV infection is present in over half the population, although age is not the only factor associated with serostatus. Knowledge of the distribution of infection in the UK population is critical for determining future vaccination policies, e.g. comparing general versus selectively targeted vaccination strategies.

Modelling the dynamics of EBV transmission to inform a vaccine target product profile and future vaccination strategy.

Epstein-Barr virus (EBV) is one of the most common human viruses and the cause of pathologies such as infectious mononucleosis (IM) and certain cancers. No vaccine against EBV infection currently exists, but such vaccines are in development. Knowledge of how EBV is transmitted at the population level is critical to the development of target product profiles (TPPs) for such vaccines and future vaccination strategies. We present the first mathematical model of EBV transmission, parameterised using data from England, and use it to compare hypothetical prophylactic vaccines with different characteristics and the impact of vaccinating different age groups. We found that vaccine duration had more impact than vaccine efficacy on modelled EBV and IM prevalence. The age group vaccinated also had an important effect: vaccinating at a younger age led to a greater reduction in seroprevalence but an increase in IM cases associated with delayed infection. Vaccination had impact on cancer incidence only in the long run, because in England most EBV-related cancers arise in later life. Durability of protection should be a key factor to prioritise in EBV vaccine development and included in vaccine TPPs. These findings are timely and important for vaccine developers and policy-makers alike.

The psychological interaction of spam email features.

This study explored distinct perceptual and decisional contributions to spam email mental construal. Participants classified spam emails according to pairings of three stimulus features - presence or absence of awkward prose, abnormal message structure, and implausible premise. We examined dimensional interactions within general recognition theory (GRT; a multidimensional extension of signal detection theory). Classification accuracy was highest for categories containing either two non-normal dimension levels (e.g. awkward prose and implausible premise) or two normal dimension levels (e.g. normal prose and plausible premise). Modelling indicated both perceptual and decisional contributions to classification responding. In most cases, perceptual discriminability was higher along one dimension when stimuli contained a non-normal level of the paired dimension (e.g. prose discriminability was higher with abnormal structure). Similarly, decision criteria along one dimension were biased in favour of the non-normal response when stimuli contained a non-normal level of the paired dimension. Potential applications for training are discussed. Practitioner summary: We applied general recognition theory (i.e. multivariate signal detection theory) to spam email classification at low or high levels of three stimulus dimensions: premise plausibility, prose quality, and email structure. Relevant to training, this approach helped identify perceptual and decisional biases that could be leveraged to individualise training.

Depth benefits now loading: Visual working memory capacity and benefits in 3-D.

The present studies explored how performance in multidimensional displays varies as a function of visual working memory load, item distribution across depths, and individual capacity differences. In Experiment 1, the benefit of depth information (one depth vs. two depths) was examined across seven set sizes within a change-detection paradigm. Multiple depth planes engendered performance benefits with five items, but elicited performance decrements with three items. These effects were associated with working memory capacity, such that benefits were only observed when the working memory load exceeded an individual's max capacity. Experiment 2 evaluated how the distribution of items in depth aids working memory performance. Equal distribution of items across depths produced higher accuracy compared with when the target was isolated in depth. Lastly, Experiment 3 explored how differences in working memory capacity affect an individual's ability to use depth information to improve their performance. The results indicate that both low-capacity and high-capacity individuals can benefit from depth information, but this may vary as a function of working memory load. Overall, the results indicate that multidimensional displays can improve performance with sufficient working memory load, possibly through some sort of depth tag.

Through the Google Glass: The impact of heads-up displays on visual attention.

In five experiments, we evaluated how secondary information presented on a heads-up display (HUD) impacts performance of a concurrent visual attention task. To do so, we had participants complete a primary visual search task under a variety of secondary load conditions (a single word presented on Google Glass during each search trial). Processing of secondary information was measured through a recognition memory task. Other manipulations included relevance (Experiments 1-4) and temporal onset of secondary information relative to the primary task (Experiment 3). Secondary information was always disruptive to the visual search, regardless of temporal onset and even when participants were instructed to ignore it. These patterns were evident in search tasks reflective of both selective (Experiments 1-3) and preattentive (Experiment 4) attentional mechanisms, and were not a result of onset-offset attentional capture (Experiment 5). Recognition memory for secondary information was always above chance. Our findings suggest that HUD-based visual information is profoundly disruptive to attentional processes and largely immune to user-centric prioritization.

Fixation not required: characterizing oculomotor attention capture for looming stimuli.

A stimulus moving toward us, such as a ball being thrown in our direction or a vehicle braking suddenly in front of ours, often represents a stimulus that requires a rapid response. Using a visual search task in which target and distractor items were systematically associated with a looming object, we explored whether this sort of looming motion captures attention, the nature of such capture using eye movement measures (overt/covert), and the extent to which such capture effects are more closely tied to motion onset or the motion itself. We replicated previous findings indicating that looming motion induces response time benefits and costs during visual search Lin, Franconeri, & Enns(Psychological Science 19(7): 686-693, 2008). These differences in response times were independent of fixation, indicating that these capture effects did not necessitate overt attentional shifts to a looming object for search benefits or costs to occur. Interestingly, we found no differences in capture benefits and costs associated with differences in looming motion type. Combined, our results suggest that capture effects associated with looming motion are more likely subserved by covert attentional mechanisms rather than overt mechanisms, and attention capture for looming motion is likely related to motion itself rather than the onset of motion.