Human factors/ergonomics to support the design and testing of rapidly manufactured ventilators in the UK during the COVID-19 pandemic.

BACKGROUND: This paper describes a rapid response project from the Chartered Institute of Ergonomics & Human Factors (CIEHF) to support the design, development, usability testing and operation of new ventilators as part of the UK response during the COVID-19 pandemic. METHOD: A five-step approach was taken to (1) assess the COVID-19 situation and decide to formulate a response; (2) mobilise and coordinate Human Factors/Ergonomics (HFE) specialists; (3) ideate, with HFE specialists collaborating to identify, analyse the issues and opportunities, and develop strategies, plans and processes; (4) generate outputs and solutions; and (5) respond to the COVID-19 situation via targeted support and guidance. RESULTS: The response for the rapidly manufactured ventilator systems (RMVS) has been used to influence both strategy and practice to address concerns about changing safety standards and the detailed design procedure with RMVS manufacturers. CONCLUSION: The documents are part of a wider collection of HFE advice which is available on the CIEHF COVID-19 website (https://covid19.ergonomics.org.uk/).

The Impact of Environmental Design on Doffing Personal Protective Equipment in a Healthcare Environment: A Formative Human Factors Trial.

OBJECTIVE To explore the impact of environmental design on doffing personal protective equipment in a simulated healthcare environment. METHODS A mixed-methods approach was used that included human-factors usability testing and qualitative questionnaire responses. A patient room and connecting anteroom were constructed for testing purposes. This experimental doffing area was designed to overcome the environmental failures identified in a previous study and was not constructed based on any generalizable hospital standard. RESULTS In total, 72 healthcare workers from Ontario, Canada, took part in the study and tested the simulated doffing area. The following environmental design changes were tested and were deemed effective: increasing prominence of color-coded zones; securing disinfectant wipes and hand sanitizer; outlining disposal bins locations; providing mirrors to detect possible contamination; providing hand rails to assist with doffing; and restricting the space to doff. Further experimentation and iterative design are required with regard to several important features: positioning the disposal bins for safety, decreasing the risk of contamination and user accessibility; optimal positioning of mirrors for safety; communication within the team; and positioning the secondary team member for optimal awareness. Additional design suggestions also emerged during this study, and they require future investigation. CONCLUSIONS This study highlights the importance of the environment on doffing personal protective equipment in a healthcare setting. Iterative testing and modification of the design of the environment (doffing area) are important to enhancing healthcare worker safety. Infect Control Hosp Epidemiol 2017;38:712-717.

Personal Protective Equipment for Infectious Disease Preparedness: A Human Factors Evaluation.

OBJECTIVE To identify issues during donning and doffing of personal protective equipment (PPE) for infectious diseases and to inform PPE procurement criteria and design. DESIGN A mixed methods approach was used. Usability testing assessed the appropriateness, potential for errors, and ease of use of various combinations of PPE. A qualitative constructivist approach was used to analyze participant feedback. SETTING Four academic health sciences centers: 2 adult hospitals, 1 trauma center, and 1 pediatric hospital, in Toronto, Canada. PARTICIPANTS Participants (n=82) were representative of the potential users of PPE within Western healthcare institutions. RESULTS None of the tested combinations provided a complete solution for PPE. Environmental factors, such as anteroom layout, and the design of protocols and instructional material were also found to impact safety. The study identified the need to design PPE as a complete system, rather than mixing and matching components. CONCLUSIONS Healthcare institutions are encouraged to use human factors methods to identify risk and failure points with the usage of their selected PPE, and to modify on the basis of iterative evaluations with representative end users. Manufacturers of PPE should consider usability when designing the next generation of PPE. Infect Control Hosp Epidemiol 2016;37:1022-1028.

Action modulated cognition: the influence of sensori-motor experience on the global processing bias.

Whether we are aware of it or not, cognition is inherently biased. Researchers have attempted to modulate these biases using prism adaptation in both healthy and patient populations. Recent research suggests that prisms themselves might not be necessary; simply interacting with one side of space can produce similar effects (Dupierrix, Alleysson, Ohlmann and Chokron (2008). Brain Research, 1214, 127-135). Here we tested whether sensori-motor interaction with the environment affects aspects of cognition that should at first glance appear to be unrelated. While previous research involved tasks that were largely directional in nature (e.g., line bisection), we chose a task without a directional component, the hierarchical figures task (Navon, (1977). Cognitive Psychology, 9, 353-383). In a sample of healthy young adults, we found that after 5min of lateralized pointing (pointing solely to the left or right side of space), performance on the hierarchical figures task varied significantly as a function of pointing direction: interference from irrelevant global information increased after interacting with the left side of space and decreased after interacting with the right side of space. We discuss the results in relation to a "hemispheric imbalance" hypothesis. Our findings demonstrate that cognition can be readily influenced by interactions with the environment even without artificially distorting normal perceptuo-motor relationships.

Terminal, but not concurrent prism exposure produces perceptual aftereffects in healthy young adults.

A short period of prism adaptation (PA) has been shown to reduce spatial neglect symptoms. Recent evidence suggests that the positive effects of PA might be restricted to visually guided actions, with PA having little effect on perception. However, the majority of studies have adopted a concurrent exposure technique that fosters the development of a change in felt arm position (proprioceptive straight ahead, PSA). Few studies have used terminal exposure that promotes a change in the perceived visual direction (visual straight ahead, VSA). The positive effects of PA might appear to be primarily action based because studies have adopted an exposure technique that promotes a change in proprioception. Here, we compare the effects of the two exposure types on a perceptual and a manual line bisection task in healthy young adults. Before and after seven minutes of exposure to leftward displacing prisms we measured performance on two line bisection tasks (manual and perceptual) and perceived straight ahead (PSA and VSA). During the exposure period participants made pointing movements while the view of their pointing arm was either (i) restricted to the second half of the pointing movement (concurrent exposure) or (ii) restricted to the final part of the pointing movement (terminal exposure). In line with the previous research, concurrent exposure produced a large shift in PSA and a shift on the manual line bisection task. Interestingly, terminal exposure produced a large shift in VSA and a shift in performance on the perceptual line bisection task. Our results shed light on the underlying mechanisms of prism-induced neglect recovery and help to address an apparent discrepancy within the literature.

The role of discrepant retinal motion during walking in the realignment of egocentric space.

Visually guided action relies on accurate perception of egocentric direction. Unfortunately, perceived direction easily becomes misaligned. How is this problem overcome? One theory (R. Held & S. J. Freedman, 1963) is that during self-movement the observer uses the relationship between anticipated and experienced sensory feedback as a source of information to maintain alignment. However, data supporting this theory is equivocal, and recent evidence appears contradictory. We reexamined the issue. We injected an error into perceived visual direction and then assessed realignment after a period of walking toward a target. We manipulated the sensory information available (presence of retinal motion, Experiment 1; presence of peripheral motion, Experiment 2) and found that as the amount of retinal motion was reduced (Experiments 1 and 2), realignment of perceived visual direction decreased. When we then (Experiment 3) removed the discrepancy between anticipated and experienced retinal motion, no realignment was observed. Our results provide evidence that a discrepancy between anticipated and experienced sensory feedback is an important source of information for the alignment of egocentric space, with retinal motion having a particular role in driving a realignment of perceived visual direction.