Local but not global graph theoretic measures of semantic networks generalize across tasks.

"Dogs" are connected to "cats" in our minds, and "backyard" to "outdoors." Does the structure of this semantic knowledge differ across people? Network-based approaches are a popular representational scheme for thinking about how relations between different concepts are organized. Recent research uses graph theoretic analyses to examine individual differences in semantic networks for simple concepts and how they relate to other higher-level cognitive processes, such as creativity. However, it remains ambiguous whether individual differences captured via network analyses reflect true differences in measures of the structure of semantic knowledge, or differences in how people strategically approach semantic relatedness tasks. To test this, we examine the reliability of local and global metrics of semantic networks for simple concepts across different semantic relatedness tasks. In four experiments, we find that both weighted and unweighted graph theoretic representations reliably capture individual differences in local measures of semantic networks (e.g., how related pot is to pan versus lion). In contrast, we find that metrics of global structural properties of semantic networks, such as the average clustering coefficient and shortest path length, are less robust across tasks and may not provide reliable individual difference measures of how people represent simple concepts. We discuss the implications of these results and offer recommendations for researchers who seek to apply graph theoretic analyses in the study of individual differences in semantic memory.

A quantitative model of ensemble perception as summed activation in feature space.

Ensemble perception is a process by which we summarize complex scenes. Despite the importance of ensemble perception to everyday cognition, there are few computational models that provide a formal account of this process. Here we develop and test a model in which ensemble representations reflect the global sum of activation signals across all individual items. We leverage this set of minimal assumptions to formally connect a model of memory for individual items to ensembles. We compare our ensemble model against a set of alternative models in five experiments. Our approach uses performance on a visual memory task for individual items to generate zero-free-parameter predictions of interindividual and intraindividual differences in performance on an ensemble continuous-report task. Our top-down modelling approach formally unifies models of memory for individual items and ensembles and opens a venue for building and comparing models of distinct memory processes and representations.

There Is no Theory-Free Measure of "Swaps" in Visual Working Memory Experiments.

Visual working memory is highly limited, and its capacity is tied to many indices of cognitive function. For this reason, there is much interest in understanding its architecture and the sources of its limited capacity. As part of this research effort, researchers often attempt to decompose visual working memory errors into different kinds of errors, with different origins. One of the most common kinds of memory error is referred to as a "swap," where people report a value that closely resembles an item that was not probed (e.g., an incorrect, non-target item). This is typically assumed to reflect confusions, like location binding errors, which result in the wrong item being reported. Capturing swap rates reliably and validly is of great importance because it permits researchers to accurately decompose different sources of memory errors and elucidate the processes that give rise to them. Here, we ask whether different visual working memory models yield robust and consistent estimates of swap rates. This is a major gap in the literature because in both empirical and modeling work, researchers measure swaps without motivating their choice of swap model. Therefore, we use extensive parameter recovery simulations with three mainstream swap models to demonstrate how the choice of measurement model can result in very large differences in estimated swap rates. We find that these choices can have major implications for how swap rates are estimated to change across conditions. In particular, each of the three models we consider can lead to differential quantitative and qualitative interpretations of the data. Our work serves as a cautionary note to researchers as well as a guide for model-based measurement of visual working memory processes.

Factors that influence the administration of tranexamic acid (TXA) to trauma patients in prehospital settings: a systematic review.

OBJECTIVE: In the UK there are around 5400 deaths annually from injury. Tranexamic acid (TXA) prevents bleeding and has been shown to reduce trauma mortality. However, only 5% of UK major trauma patients who are at risk of haemorrhage receive prehospital TXA. This review aims to examine the evidence regarding factors influencing the prehospital administration of TXA to trauma patients. DESIGN: Systematic literature review. DATA SOURCES: AMED, CENTRAL, CINAHL, Cochrane Database of Systematic Reviews, Conference Proceedings Citation Index-Science, Embase and MEDLINE were searched from January 2010 to 2020; searches were updated in June 2022. CLINICALTRIALS: gov and OpenGrey were also searched and forward and backwards citation chasing performed. ELIGIBILITY CRITERIA: All primary research reporting factors influencing TXA administration to trauma patients in the prehospital setting was included. DATA EXTRACTION AND SYNTHESIS: Two independent reviewers performed the selection process, quality assessment and data extraction. Data were tabulated, grouped by setting and influencing factor and synthesised narratively. RESULTS: Twenty papers (278 249 participants in total) were included in the final synthesis; 13 papers from civilian and 7 from military settings. Thirteen studies were rated as 'moderate' using the Effective Public Health Practice Project Quality Assessment Tool. Several common factors were identified: knowledge and skills; consequences and social influences; injury type (severity, injury site and mechanism); protocols; resources; priorities; patient age; patient sex. CONCLUSIONS: This review highlights an absence of high-quality research. Preliminary evidence suggests a host of system and individual-level factors that may be important in determining whether TXA is administered to trauma patients in the prehospital setting. FUNDING AND REGISTRATION: This review was supported by Research Capability Funding from the South Western Ambulance Service NHS Foundation Trust and the National Institute for Health Research Applied Research Collaboration South West Peninsula. PROSPERO REGISTRATION NUMBER: CRD42020162943.

Linking computational models of two core tasks of cognitive control.

Cognitive control refers to the ability to maintain goal-relevant information in the face of distraction, making it a core construct for understanding human thought and behavior. There is great theoretical and practical value in building theories that can be used to explain or to predict variations in cognitive control as a function of experimental manipulations or individual differences. A critical step toward building such theories is determining which latent constructs are shared between laboratory tasks that are designed to measure cognitive control. In the current work, we examine this question in a novel way by formally linking computational models of two canonical cognitive control tasks, the Eriksen flanker and task-switching task. Specifically, we examine whether model parameters that capture cognitive control processes in one task can be swapped across models to make predictions about individual differences in performance on another task. We apply our modeling and analysis to a large scale data set from an online cognitive training platform, which optimizes our ability to detect individual differences in the data. Our results suggest that the flanker and task-switching tasks probe common control processes. This finding supports the view that higher level cognitive control processes as opposed to solely strategies in speed and accuracy tradeoffs, or perceptual processing and motor response speed are shared across the two tasks. We discuss how our computational modeling substitution approach addresses limitations of prior efforts to relate performance across different cognitive control tasks, and how our findings inform current theories of cognitive control. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Measuring memory is harder than you think: How to avoid problematic measurement practices in memory research.

We argue that critical areas of memory research rely on problematic measurement practices and provide concrete suggestions to improve the situation. In particular, we highlight the prevalence of memory studies that use tasks (like the "old/new" task: "have you seen this item before? yes/no") where quantifying performance is deeply dependent on counterfactual reasoning that depends on the (unknowable) distribution of underlying memory signals. As a result of this difficulty, different literatures in memory research (e.g., visual working memory, eyewitness identification, picture memory, etc.) have settled on a variety of fundamentally different metrics to get performance measures from such tasks (e.g., A', corrected hit rate, percent correct, d', diagnosticity ratios, K values, etc.), even though these metrics make different, contradictory assumptions about the distribution of latent memory signals, and even though all of their assumptions are frequently incorrect. We suggest that in order for the psychology and neuroscience of memory to become a more cumulative, theory-driven science, more attention must be given to measurement issues. We make a concrete suggestion: The default memory task for those simply interested in performance should change from old/new ("did you see this item'?") to two-alternative forced-choice ("which of these two items did you see?"). In situations where old/new variants are preferred (e.g., eyewitness identification; theoretical investigations of the nature of memory signals), receiver operating characteristic (ROC) analysis should be performed rather than a binary old/new task.

What Your Dermatopathologist Wants You to Know.

The skin biopsy and histologic examination are an important part of providing dermatologic care. Effective communication with your dermatopathologist on the biopsy requisition form helps provide clinicopathological correlation and facilitates accurate and timely histopathologic diagnosis of the biopsy.

Direct Immunofluorescence.

Direct immunofluorescence (DIF) is a valuable diagnostic tool in the dermatology clinic. The proper use of a biopsy for DIF is dependent on several factors, including appropriate clinical indication, correct clinical site selection, and proper specimen handling and transport. Improper use of DIF can lead to false negatives, decreased diagnostic yield, and poor resource utilization. This article provides instruction on the appropriate indications and biopsy site selection for DIF. Three examples of skin diseases in which DIF would be particular useful when making a diagnosis are provided.

You cannot "count" how many items people remember in visual working memory: The importance of signal detection-based measures for understanding change detection performance.

Change detection tasks are commonly used to measure and understand the nature of visual working memory capacity. Across three experiments, we examine whether the nature of the memory signals used to perform change detection are continuous or all-or-none and consider the implications for proper measurement of performance. In Experiment 1, we find evidence from confidence reports that visual working memory is continuous in strength, with strong support for an equal variance signal detection model with no guesses or lapses. Experiments 2 and 3 test an implication of this, which is that K should confound response criteria and memory. We found K values increased by roughly 30% when criteria are shifted despite no change in the underlying memory signals. Overall, our data call into question a large body of work using threshold measures, like K, to analyze change detection data. This metric confounds response bias with memory performance and is inconsistent with the vast majority of visual working memory models, which propose variations in precision or strength are present in working memory. Instead, our data indicate an equal variance signal detection model (and thus, d')-without need for lapses or guesses-is sufficient to explain change detection performance. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Amplification in the evaluation of multiple emotional expressions over time.

Social interactions are dynamic and unfold over time. To make sense of social interactions, people must aggregate sequential information into summary, global evaluations. But how do people do this? Here, to address this question, we conducted nine studies (N = 1,583) using a diverse set of stimuli. Our focus was a central aspect of social interaction-namely, the evaluation of others' emotional responses. The results suggest that when aggregating sequences of images and videos expressing varying degrees of emotion, perceivers overestimate the sequence's average emotional intensity. This tendency for overestimation is driven by stronger memory of more emotional expressions. A computational model supports this account and shows that amplification cannot be explained only by nonlinear perception of individual exemplars. Our results demonstrate an amplification effect in the perception of sequential emotional information, which may have implications for the many types of social interactions that involve repeated emotion estimation.

Clinical and Serological Features in Latin American IgG4-Related Disease Patients Differ According to Sex, Ethnicity, and Clinical Phenotype.

BACKGROUND/OBJECTIVE: Data on IgG4-related disease (IgG4-RD) come almost exclusively from cohorts from Asia, Europe, and North America. We conducted this study to describe the clinical presentation, phenotype distribution, and association with sex, ethnicity, and serological markers in a large cohort of Latin American patients with IgG4-RD. METHODS: We performed a multicenter medical records review study including 184 Latin American IgG4-RD patients. We assigned patients to clinical phenotypes: group 1 (pancreato-hepato-biliary), group 2 (retroperitoneal/aortic), group 3 (head and neck-limited), group 4 (Mikulicz/systemic), and group 5 (undefined). We focused the analysis on how sex, ethnicity, and clinical phenotype may influence the clinical and serological presentation. RESULTS: The mean age was 50.8 ± 15 years. Men and women were equally affected (52.2% vs 48.8%). Fifty-four patients (29.3%) were assigned to group 1, 21 (11.4%) to group 2, 57 (30.9%) to group 3, 32 (17.4%) to group 4, and 20 (10.8%) to group 5. Male sex was associated with biliary tract (odds ratio [OR], 3.4; 95% confidence interval [CI], 1.36-8.26), kidney (OR, 3.4; 95% CI, 1.28-9.25), and retroperitoneal involvement (OR, 5.3; 95% CI, 1.45-20). Amerindian patients presented more frequently with atopy history and gallbladder involvement. Group 3 had a female predominance. CONCLUSIONS: Latin American patients with IgG4-RD were younger, and men and women were equally affected compared with White and Asian cohorts. They belonged more commonly to group 1 and group 3. Retroperitoneal and aortic involvement was infrequent. Clinical and serological features differed according to sex, ethnicity, and clinical phenotype.

Supraglottic airway device versus tracheal intubation in the initial airway management of out-of-hospital cardiac arrest: the AIRWAYS-2 cluster RCT.

BACKGROUND: When a cardiac arrest occurs, cardiopulmonary resuscitation should be started immediately. However, there is limited evidence about the best approach to airway management during cardiac arrest. OBJECTIVE: The objective was to determine whether or not the i-gel® (Intersurgical Ltd, Wokingham, UK) supraglottic airway is superior to tracheal intubation as the initial advanced airway management strategy in adults with non-traumatic out-of-hospital cardiac arrest. DESIGN: This was a pragmatic, open, parallel, two-group, multicentre, cluster randomised controlled trial. A cost-effectiveness analysis accompanied the trial. SETTING: The setting was four ambulance services in England. PARTICIPANTS: Patients aged ≥ 18 years who had a non-traumatic out-of-hospital cardiac arrest and were attended by a participating paramedic were enrolled automatically under a waiver of consent between June 2015 and August 2017. Follow-up ended in February 2018. INTERVENTION: Paramedics were randomised 1 : 1 to use tracheal intubation (764 paramedics) or i-gel (759 paramedics) for their initial advanced airway management and were unblinded. MAIN OUTCOME MEASURES: The primary outcome was modified Rankin Scale score at hospital discharge or 30 days after out-of-hospital cardiac arrest, whichever occurred earlier, collected by assessors blinded to allocation. The modified Rankin Scale, a measure of neurological disability, was dichotomised: a score of 0-3 (good outcome) or 4-6 (poor outcome/death). The primary outcome for the economic evaluation was quality-adjusted life-years, estimated using the EuroQol-5 Dimensions, five-level version. RESULTS: A total of 9296 patients (supraglottic airway group, 4886; tracheal intubation group, 4410) were enrolled [median age 73 years; 3373 (36.3%) women]; modified Rankin Scale score was known for 9289 patients. Characteristics were similar between groups. A total of 6.4% (311/4882) of patients in the supraglottic airway group and 6.8% (300/4407) of patients in the tracheal intubation group had a good outcome (adjusted difference in proportions of patients experiencing a good outcome: -0.6%, 95% confidence interval -1.6% to 0.4%). The supraglottic airway group had a higher initial ventilation success rate than the tracheal intubation group [87.4% (4255/4868) vs. 79.0% (3473/4397), respectively; adjusted difference in proportions of patients: 8.3%, 95% confidence interval 6.3% to 10.2%]; however, patients in the tracheal intubation group were less likely to receive advanced airway management than patients in the supraglottic airway group [77.6% (3419/4404) vs. 85.2% (4161/4883), respectively]. Regurgitation rate was similar between the groups [supraglottic airway group, 26.1% (1268/4865); tracheal intubation group, 24.5% (1072/4372); adjusted difference in proportions of patients: 1.4%, 95% confidence interval -0.6% to 3.4%], as was aspiration rate [supraglottic airway group, 15.1% (729/4824); tracheal intubation group, 14.9% (647/4337); adjusted difference in proportions of patients: 0.1%, 95% confidence interval -1.5% to 1.8%]. The longer-term outcomes were also similar between the groups (modified Rankin Scale: at 3 months, odds ratio 0.89, 95% confidence interval 0.69 to 1.14; at 6 months, odds ratio 0.91, 95% confidence interval 0.71 to 1.16). Sensitivity analyses did not alter the overall findings. There were no unexpected serious adverse events. Mean quality-adjusted life-years to 6 months were 0.03 in both groups (supraglottic airway group minus tracheal intubation group difference -0.0015, 95% confidence interval -0.0059 to 0.0028), and total costs were £157 (95% confidence interval -£270 to £583) lower in the tracheal intubation group. Although the point estimate of the incremental cost-effectiveness ratio suggested that tracheal intubation may be cost-effective, the huge uncertainty around this result indicates no evidence of a difference between groups. LIMITATIONS: Limitations included imbalance in the number of patients in each group, caused by unequal distribution of high-enrolling paramedics; crossover between groups; and the fact that participating paramedics, who were volunteers, might not be representative of all paramedics in the UK. Findings may not be applicable to other countries. CONCLUSION: Among patients with out-of-hospital cardiac arrest, randomisation to the supraglottic airway group compared with the tracheal intubation group did not result in a difference in outcome at 30 days. There were no notable differences in costs, outcomes and overall cost-effectiveness between the groups. FUTURE WORK: Future work could compare alternative supraglottic airway types with tracheal intubation; include a randomised trial of bag mask ventilation versus supraglottic airways; and involve other patient populations, including children, people with trauma and people in hospital. TRIAL REGISTRATION: This trial is registered as ISRCTN08256118. FUNDING: This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and supported by the NIHR Comprehensive Research Networks and will be published in full in Health Technology Assessment; Vol. 26, No. 21. See the NIHR Journals Library website for further project information.

BACKGROUND: Cardiac arrest is a serious medical emergency in which the heartbeat and breathing stop suddenly. Every year in the UK, a large number of patients (around 123 per 100,000) suffer a cardiac arrest outside hospital. Only 7­9% of these patients survive to leave hospital. The best initial treatment in cardiac arrest is cardiopulmonary resuscitation (commonly known as CPR), during which it is vital to give chest compressions and maintain a clear airway. Two main techniques are used to keep the airway clear: tracheal intubation (inserting a breathing tube into the windpipe) and a supraglottic airway device (a newer device that is inserted less deeply and sits just above the voicebox). Both techniques are used routinely by paramedics in the UK when treating a cardiac arrest, but there is no evidence about which technique is best. The AIRWAYS-2 trial aimed to find out whether or not a supraglottic airway device is better than tracheal intubation. WHO PARTICIPATED AND WHAT WAS INVOLVED?: Paramedics from four UK ambulance services were put into one of two groups at random. One group was randomly chosen to use tracheal intubation and the other group was randomly chosen to use a supraglottic airway device at all adult cardiac arrests they attended for approximately 2 years. Paramedics were able to apply their clinical judgement and use a different device if they felt that this would be best for the patient. A total of 1523 paramedics took part and enrolled 9296 patients. Following cardiac arrest, a patient's recovery was assessed as good or poor (including patients who did not survive). WHAT DID THE TRIAL FIND?: A similar percentage of patients in both groups had a good recovery. There was no evidence to suggest that the supraglottic airway device was any better than tracheal intubation for treating a cardiac arrest.

Barriers and facilitators to the administration of prehospital tranexamic acid: a paramedic interview study using the theoretical domains framework.

BACKGROUND: Tranexamic acid (TXA) is an antifibrinolytic drug used to prevent bleeding. It was introduced as an intervention for post-traumatic haemorrhage across emergency medical services (EMS) in the UK during 2012. However, despite strong evidence of effectiveness, prehospital TXA administration rates are low. This study used the theoretical domains framework (TDF) to identify barriers and facilitators to the administration of TXA to trauma patients by EMS providers (paramedics) in the UK. METHODS: Interviews were completed with 18 UK paramedics from a single EMS provider organisation. A convenience sampling approach was used, and interviews continued until thematic saturation was reached. Semistructured telephone interviews explored paramedics' experiences of administering TXA to trauma patients, including identifying whether or not patients were at risk of bleeding. Data were analysed inductively using thematic analysis (stage 1). Themes were mapped to the theoretical domains of the TDF to identify behavioural theory-derived barriers and facilitators to the administration of TXA to trauma patients (stage 2). Belief statements were identified and assessed for importance according to prevalence, discordance and evidence base (stage 3). RESULTS: Barriers and facilitators to paramedics' administration of TXA to trauma patients were represented by 11 of the 14 domains of the TDF. Important barriers included a lack of knowledge and experience with TXA (Domain: Knowledge and Skills), confusion and restrictions relating to the guidelines for TXA administration (Domain: Social/professional role and identity), a lack of resources (Domain: Environmental context and resources) and difficulty in identifying patients at risk of bleeding (Domain: Memory, attention and decision processes). CONCLUSIONS: This study presents a behavioural theory-based approach to identifying barriers and facilitators to the prehospital administration of TXA to trauma patients in the UK. It identifies multiple influencing factors that may serve as a basis for developing an intervention to increase prehospital administration of TXA.

Memory Fidelity Reveals Qualitative Changes in Interactions Between Items in Visual Working Memory.

Memory for objects in a display sometimes reveals attraction-the objects are remembered as more similar to one another than they actually were-and sometimes reveals repulsion-the objects are remembered as more different from one another. The conditions that lead to these opposing memory biases are poorly understood; there is no theoretical framework that explains these contrasting dynamics. In three experiments (each N = 30 adults), we demonstrate that memory fidelity provides a unifying dimension that accommodates the existence of both types of visual working memory interactions. We show that either attraction or repulsion can arise simply as a function of manipulations of memory fidelity. We also demonstrate that subjective ratings of fidelity predict the presence of attraction or repulsion on a trial-by-trial basis. We discuss how these results bear on computational models of visual working memory and contextualize these results within the literature of attraction and repulsion effects in long-term memory and perception.

Cost-effectiveness of the i-gel supraglottic airway device compared to tracheal intubation during out-of-hospital cardiac arrest: Findings from the AIRWAYS-2 randomised controlled trial.

AIM: Optimal airway management during out-of-hospital cardiac arrest (OHCA) is uncertain. Complications from tracheal intubation (TI) may be avoided with supraglottic airway (SGA) devices. The AIRWAYS-2 cluster randomised controlled trial (ISRCTN08256118) compared the i-gel SGA with TI as the initial advanced airway management (AAM) strategy by paramedics treating adults with non-traumatic OHCA. This paper reports the trial cost-effectiveness analysis. METHODS: A within-trial cost-effectiveness analysis of the i-gel compared with TI was conducted, with a six-month time horizon, from the perspective of the UK National Health Service (NHS) and personal social services. The primary outcome measure was quality-adjusted life years (QALYs), estimated using the EQ-5D-5L questionnaire. Multilevel linear regression modelling was used to account for clustering by paramedic when combining costs and outcomes. RESULTS: 9296 eligible patients were attended by 1382 trial paramedics and enrolled in the AIRWAYS-2 trial (4410 TI, 4886 i-gel). Mean QALYs to six months were 0.03 in both groups (i-gel minus TI difference -0.0015, 95% CI -0.0059 to 0.0028). Total costs per participant up to six months post-OHCA were £3570 and £3413 in the i-gel and TI groups respectively (mean difference £157, 95% CI -£270 to £583). Based on mean difference point estimates, TI was more effective and less costly than i-gel; however differences were small and there was great uncertainty around these results. CONCLUSION: The small differences between groups in QALYs and costs shows no difference in the cost-effectiveness of the i-gel and TI when used as the initial AAM strategy in adults with non-traumatic OHCA.

The effect of lineup size on eyewitness identification.

Eyewitness identification via lineup procedures is an important and widely used source of evidence in criminal cases. However, the scientific literature provides inconsistent guidance on a very basic feature of lineup procedure: lineup size. In two experiments, we examined whether the number of fillers affects diagnostic accuracy in a lineup, as assessed with receiver-operating characteristic (ROC) analysis. Showups (identification procedures with one face) led to lower discriminability than simultaneous lineups. However, in neither experiment did the number of fillers in a lineup affect discriminability. We also evaluated competing models of decision-making from lineups. This analysis indicated that the standard Independent Observations (IO) model, which assumes a decision rule based on the comparison of memory strength signals generated by each face in a lineup, is incapable of reproducing the lower level of performance evident in showups. We could not adjudicate between the Ensemble model, which assumes a decision rule based on the comparison of the strength of each face with the mean strength across the lineup, and a newly introduced Dependent Observations model, which adopts the same decision rule as the IO model, but with correlated signals across faces. We draw lessons for users of lineup procedures and for basic research on eyewitness decision making. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Knowledge, skills and attitudes of older people and staff about getting up from the floor following a fall: a qualitative investigation.

BACKGROUND: Falls are the most common reason for ambulance callouts resulting in non-conveyance. Even in the absence of injury, only half of those who fall can get themselves up off the floor, often remaining there over an hour, increasing risk of complications. There are recognized techniques for older people to learn how to get up after a fall, but these are rarely taught. The aim of this study was to develop an understanding of attitudes of older people, carers and health professionals on getting up following a fall. METHODS: A qualitative focus group and semi-structured interviews were conducted with 28 participants, including community-dwelling older people with experience of a non-injurious fall, carers, physiotherapists, occupational therapists, paramedics and first responders. Data were transcribed and analysed systematically using the Framework approach. A stakeholder group of falls experts and service users advised during analysis. RESULTS: The data highlighted three areas contributing to an individual's capability to get-up following a fall: the environment (physical and social); physical ability; and degree of self-efficacy (attitude and beliefs about their own ability). These factors fell within the wider context of making a decision about needing help, which included what training and knowledge each person already had to manage their fall response. Staff described how they balance their responsibilities, prioritising the individual's immediate needs; this leaves limited time to address capability in the aforementioned three areas. Paramedics, routinely responding to falls, only receive training on getting-up techniques from within their peer-group. Therapists are aware of the skillset to breakdown the getting-up process, but, with limited time, select who to teach these techniques to. CONCLUSION: Neither therapists nor ambulance service staff routinely teach strategies on how to get up, meaning that healthcare professionals largely have a reactive role in managing falls. Interventions that address the environment, physical ability and self-efficacy could positively impact on peoples' capability to get up following a fall. Therefore, a more proactive approach would be to teach people techniques to manage these aspects of future falls and to provide them easily accessible information.

Randomized trial of the i-gel supraglottic airway device versus tracheal intubation during out of hospital cardiac arrest (AIRWAYS-2): Patient outcomes at three and six months.

AIM: The AIRWAYS-2 cluster randomised controlled trial compared the i-gel supraglottic airway device (SGA) with tracheal intubation (TI) as the first advanced airway management (AAM) strategy used by Emergency Medical Service clinicians (paramedics) treating adult patients with non-traumatic out-of-hospital cardiac arrest (OHCA). It showed no difference between the two groups in the primary outcome of modified Rankin Scale (mRS) score at 30 days/hospital discharge. This paper reports outcomes to 6 months. METHODS: Paramedics from four ambulance services in England were randomised 1:1 to use an i-gel SGA (759 paramedics) or TI (764 paramedics) as their initial approach to AAM. Adults who had a non-traumatic OHCA and were attended by a participating paramedic were enrolled automatically under a waiver of consent. Survivors were invited to complete questionnaires at three and six months after OHCA. Outcomes were analysed using regression methods. RESULTS: 767/9296 (8.3%) enrolled patients survived to 30 days/hospital discharge and 317/767 survivors (41.3%) consented and were followed-up to six months. No significant differences were found between the two treatment groups in the primary outcome measure (mRS score: 3 months: odds ratio (OR) for good recovery (i-gel/TI, OR) 0.89, 95% CI 0.69-1.14; 6 months OR 0.91, 95% CI 0.71-1.16). EQ-5D-5L scores were also similar between groups and sensitivity analyses did not alter the findings. CONCLUSION: There were no statistically significant differences between the TI and i-gel groups at three and six months. We therefore conclude that the initially reported finding of no significant difference between groups at 30 days/hospital discharge was sustained when the period of follow-up was extended to six months.

Is there a K in capacity? Assessing the structure of visual short-term memory.

Visual short-term memory (VSTM) is a cognitive structure that temporarily maintains a limited amount of visual information in the service of current cognitive goals. There is active theoretical debate regarding how limits in VSTM should be construed. According to discrete-slot models of capacity, these limits are set in terms of a discrete number of slots that store individual objects in an all-or-none fashion. According to alternative continuous resource models, the limits of VSTM are set in terms of a resource that can be distributed to bolster some representations over others in a graded fashion. Hybrid models have also been proposed. We tackled the classic question of how to construe VSTM structure in a novel way, by examining how contending models explain data within traditional VSTM tasks and also how they generalize across different VSTM tasks. Specifically, we fit theoretical ROCs derived from a suite of models to two popular VSTM tasks: a change detection task in which participants had to remember simple features and a rapid serial visual presentation task in which participants had to remember real-world objects. In 3 experiments we assessed the fit and predictive ability of each model and found consistent support for pure resource models of VSTM. To gain a fuller understanding of the nature of limits in VSTM, we also evaluated the ability of these models to jointly model the two tasks. These joint modeling analyses revealed additional support for pure continuous-resource models, but also evidence that performance across the two tasks cannot be captured by a common set of parameters. We provide an interpretation of these signal detection models that align with the idea that differences among memoranda and across encoding conditions alter the memory signal of representations in VSTM.