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Background: Work-related musculoskeletal disorders (WMSDs) affect a significant percentage of the neurosurgical workforce. The aim of the current questionnaire-based study was to examine the prevalence of WMSDs amongst neurosurgeons, identify risk factors, and study the views of neurosurgeons regarding ergonomics., Methods: From June to August 2020, members of the "European Association of Neurosurgical Societies," the "Neurosurgery Research Listserv," and the "Latin American Federation of Neurosurgical Societies" were asked to complete an electronic questionnaire on the topics of WMSDs and ergonomics., Results: A total of 409 neurosurgeons responded to the survey, with a 4.7 male to female ratio. Most of the surgeons worked in Europe (76.9%) in academic public hospitals. The vast majority of the participants (87.9%) had experienced WMSDs, mainly affecting the shoulder, neck, and back muscles. The most common operations performed by the participants were "Craniotomy for convexity/intrinsic tumors" (24.1%) and "Open lumbar basic spine" (24.1%). Neurosurgeons agreed that ergonomics is an underexposed area in the neurosurgical field (84.8%) and that more resources should be spend (87.3%) and training curricula changes should be made (78.3%) in order to alleviate the burden of WMSDs on neurosurgeons. Univariate analysis did not reveal any associations between the development of WMSDs and age, gender, tenure, average duration of operation, operating time per week, type of operation, and surgical approach., Conclusions: The problem of WMSDs ought to be more closely addressed and managed by the neurosurgical community. More studies ought to be designed to investigate specific ergonomic parameters in order to formulate practice recommendations.

Background: The school is one of the most critical social, educational, and training institutions and the main pillar of education in society. Education and, consequently, educational environments have the highest effect on the mentality, development, growth, welfare, concentration, performance, and learning efficiency of students., Objectives: The present study aimed to examine the effects of environmental ergonomics on the learning and cognition of pre-school students during the COVID-19 pandemic., Methods: The study was carried out as a review article using some keywords, namely "children", "learning", "pre-school", "COVID-19", "ergonomics", and "environmental factors". Scopus, PubMed, Science Direct and Web of Science were searched to find related articles., Results: Factors like color, form, and layout of classrooms, lighting and ventilation, interior decoration, and educational equipment are effective in creating interest and motivation for students to learn., Conclusions: A review of these articles showed that the presence of ergonomics in educational spaces for children increases the quality of learning and reduces stress and anxiety, and by observing health protocols, a healthy and safe environment can be provided for students.

Introduction: Injuries and work-related musculoskeletal disorders (MSDs) are common among masons. SAfety Voice for Ergonomics (SAVE) integrates training in ergonomic and safety problem-solving skills into masonry apprenticeship training. The purpose of this study was to assess the efficacy of text messaging to reinforce SAVE program content., Method: SAVE effectiveness was evaluated at masonry apprenticeship training centers across the United States by comparing three experimental groups: (1) Ergonomics training, (2) Ergonomics and Safety Voice training, and a (3) Control. Apprentices received SAVE training with their standard instruction. To reinforce classroom training, refresher training was implemented by sending weekly text messages for six months. Half of the text messages required a response, which tested knowledge or assessed behavior, while the remaining reiterated knowledge. Apprentices (n = 119) received SAVE text messages. Response rates and percentage of correct responses were compared with chi-square tests and independent group t-tests. Multivariable logistic regression analysis predicted apprentice response with selected demographic and work experience variables. Finally, feedback on of the use of text messaging was obtained., Result: Of 119 participants, 61% (n = 72) responded to at least one text message. Logistic regression revealed that being a high school graduate and a brick and block mason significantly affected the odds of responding. Sixty-nine percent of apprentices agreed that text messages reinforced SAVE content., Conclusion: Even though there was no training center requirement to respond, the high response rate suggests that text messaging can effectively be used to reinforce ergonomics and safety voice training for both knowledge and behavior. Practical Application: The prevalent use of text messaging creates opportunities to reinforce health and safety training and engage workers, especially for populations that may be at various locations over time such as construction sites. Instructors and practitioners should consider the utility of text messaging for supporting their training and safety programs., (Copyright © 2020. Published by Elsevier Ltd.)

Aim: The aim of this study was to assess the prevalence of computer vision syndrome (CVS) and its associated ergonomic factors among university administrative staff in Ghana., Methods: A cross-sectional survey was conducted among 200 administrative staff of the University of Cape Coast. The procedure included a self-administered questionnaire, comprehensive ocular health examination, and assessment of computer workstation and lighting conditions. The prevalence of CVS among the subjects and the association between CVS and ergonomic practices were determined., Results: The mean age of the study sample was 31.0 ± 4.7 years, and the majority were males (56.0%). The prevalence of CVS was among 103 (51.5%)participants. Over a third of the respondents used computers for 6 or more hours daily. Significant association was found between CVS and poor ergonomic practices ( χ  = 15.175, p = 0.001)., Conclusion: In addition to poor ergonomic office setup, university administrative staff spend several hours behind computer screens leading to the development of CVS. Increased awareness of CVS and adherence to recommended ergonomic practices are necessary to reduce the prevalence of CVS and ultimately enhance work satisfaction and productivity., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2020 Samuel Bert Boadi-Kusi et al.)

Background: Performing common computer tasks such as pointing, clicking, and dragging requires repetitive movements that cause musculoskeletal disorders in the wrists and hands. Given the growing use of touch screens and touch pens, further studies on the ergonomics of these devices are needed. This study aimed to compare a touch pen and an ordinary computer mouse in terms of movement time, error rate, wrist posture, and comfort of use., Methods: Performance parameters (movement time and error rate), wrist postures, and comfort when using a mouse and a touch pen were measured based on ISO 9241-9 standard with the help of 27 participants. For data analysis, paired t test was performed using SPSS version 22., Results: Using the touch pen resulted in better performance parameters than using the mouse (p < 0.05). Wrist extension and flexion were lower when performing the task with the computer mouse than with the touch pen (p < 0.05). When using the touch pen to perform the task, ulnar deviation and radial deviation were lower (p < 0.05). The overall comfort was higher when using the mouse than the touch pen., Conclusion: Our results showed that the touch pen had better performance parameters than the ordinary mouse and also resulted in lower ulnar and radial deviations. Given the impact of habit and proficiency on users' comfort in using input devices, it is reasonable to expect users becoming more comfortable by using touch pens on the long term.

This study evaluated physical ergonomic risk factors associated with carpal tunnel syndrome (CTS) among rubber tappers in Thailand. The Boston Carpal Tunnel Syndrome Questionnaire and Phalen's test and Tinel's sign were used to identify 133 cases with CTS and 401 non-CTS controls. Video recordings and Rapid Upper Limb Assessment used to evaluate the level of ergonomic risk in right and left hand postures. Significant physical ergonomic risk factors of CTS were higher number of trees tapped at or below knee level and collecting latex. Among right-handed tappers, tapping at higher than chest level involved significantly higher proportion of right wrist flexion and/or extension, and left wrist radial and/or ulnar deviation and twist than tapping at a lower level.

Background: When performing, classical guitarists interact with many elements which constitute their own "workstation". One of those elements is the support for guitar positioning. Support dimensions, form and materials may determine posture and affect the musician's comfort and performance., Objective: To propose design requirements for new supports for guitar positioning, based on postural assessment, anthropometric criteria, self-efficacy and comfort perception., Methods: Nine healthy Classical Guitar students were recruited. A postural assessment was undertaken using REBA, and 3DSSPP software with three different supports for guitar positioning. After the use of each support, a questionnaire about self-efficacy and comfort perception was completed by the participants., Results: The higher scores of risk and a significant difference (ANOVA, p =≤05) regarding the left leg elevation were found with footstool usage. However, this one was identified by participants as the best support in terms of self-efficacy and comfort assessment., Conclusions: To improve performance and prevent physical injuries for guitarists, there is a need for designing guitar positionings supports based on ergonomics principles. This paper proposes eleven guidelines for designing these supports.

Background: Working in front of computer screens is visually demanding and related to adverse eye symptoms. Occurrence of glare further increases visual fatigue., Objective: This paper presents results from an examination of visual ergonomics in control room environments at two Swedish process industries., Methods: Visual conditions were examined and evaluated in nine control rooms and eighteen process operators answered questions about their perceived workload and visual experiences., Results: When working in the control rooms, the mental workload was rated significantly higher by the participants, compared to experienced performance. The operators further experienced significantly higher visual fatigue and blurred vision compared to double vision and sore eyes. Visual demands were increased in conditions where contrast glare was present, as well as frequent changes of focusing distances, and low contrast between background and characters in computer screens., Conclusions: Suboptimal visual working conditions in the control rooms contributes to increased visual demands on the operators. Presence of glare is leading to visual fatigue and an unnecessary high mental load. The findings support the relevance of considering principles of general and visual ergonomics when designing and organizing work in control rooms. Workstation design should also be flexible to allow for individual and contextual adjustments.

Introduction: Ergonomics in ophthalmology is neither taught during professional training nor does it readily receive consideration or priority in clinical practice. Owing to a high prevalence of musculoskeletal disorders among ophthalmologists, ergonomic awareness, and practices are vital in averting this modern epidemic., Objective: To assess the ergonomic practices and prevalence of self-reported musculoskeletal disorders among ophthalmologists in India., Method: An online survey was conducted among ophthalmologists who were registered with the All India Ophthalmological Society of India using a pre-tested and validated questionnaire., Results: The prevalence of self-reported musculoskeletal disorder in the 377 participants was 75.3% (284; 95% confidence interval: 70.6-79.5). Low back pain (149, 52.9%) was the most commonly reported symptom. Musculoskeletal disorder-attributed productivity loss was reported by 58.45% (166) of the respondents. Musculoskeletal disorder was most frequently associated with less than 10 years of work experience (odds ratio: 1.2; 95% confidence interval: 1.1-1.3, p = 0.01) and lack of good clinic (odds ratio: 1.7; 95% confidence interval: 1.1-2.7, p = 0.03) and operation room ergonomic practices (odds ratio: 1.8; 95% confidence interval: 1.1-2.9, p = 0.03). Only 27.9% (105) of the respondents had accessed information related to ergonomics in ophthalmic practice., Conclusion: The self-reported musculoskeletal disorder among ophthalmologists in India is quite high and significant enough to cause some degree of productivity loss. It is thus imperative to emphasize the implementation of good ergonomic practices, especially among relatively young ophthalmologists.

Background: Approximately 2.38 million janitors are employed in the U.S. While high physical workload may explain a lost-work days rate 2.7 times greater than other occupations, little is known about the association between janitors' physical workload, mental workload, and stress., Objective: The objective of this study was to assess the associations between physical (ergonomic) and mental workload exposures and stress outcomes among janitors., Methods: Questionnaire data, focused on ergonomic workload, mental workload and stress, were collected from Minnesota janitors for a one-year period. Physical workload was assessed with Borg Scales and Rapid Entire Body Assessments (REBA). Mental workload assessment utilized the NASA Task Load Index (TLX). Stress assessments utilized single-item ordinal stress scale (SISS) and Perceived Stress Scale-4 (PSS-4) measures. Descriptive and multivariable analyses, including bias adjustment, were conducted., Results: Odds ratios (OR) and 95% confidence intervals (CI) for ergonomic workload (task frequency) effects on SISS were: REBA (1.18 OR, 1.02-1.37 CI); Borg (1.25 OR, 1.00-1.56 CI); combined REBA and Borg (1.10 OR, 1.01-1.20 CI). Mental workload was associated with higher PSS-4 levels (0.15 Mean Difference, 0.08-0.22 CI) and a 3% increased risk for each one-unit increase in the SISS scale (1.03 OR, 1.02-1.05 CI)., Conclusions: This research demonstrated a moderate effect of physical and mental workloads on stress among janitors.

Background: Students use a school bag to carry their school supplies which may not have the required standards and ergonomic factors., Objective: This study was aimed to examine the ergonomic factors of schoolbags and their adaptation to the weight of elementary school students., Methods: This cross-sectional study was carried out on 721 primary schoolchildren. To collecting data a checklist, which its final version was approved by the experts, was designed by researchers. Data were analyzed by using SPSS ver. 22 and Chi-square test, One-Way ANOVA, and univariate and multivariate logistic regression models., Results: In this study, about 90.1% of students used a backpack to carry their items and most students carried backpacks with a weight up to 10% of their body weight. In 43.5% of the students, waist width was appropriate with backpack width at the bottom, and in 96.6% shoulder width was appropriate with backpack width at the top. Multivariate logistic regression showed that girls in compared to boys were more likely tolerated ratio of backpack weight to body weight, and also had more likely proportion of waist width and the backpack width at the bottom. The grades of the first, second, and fourth used more heavy backpacks. Students who their mothers were employee compared to housewives, carried heavier backpacks and had more likely proportion of waist width and the backpack width at the bottom. As the mother's age increased, the proportion of waist width and the backpack width at the bottom is diminished., Conclusion: The schoolbags weight of many students was more than the standard weight, and their schoolbags did not have the required standards. Educational interventions can increase the knowledge of students and parents about the ideal weight of a schoolbag and the criteria for choosing a proper school bag.

Background: There is increasing availability of, and interest in, wearable activity trackers for children younger than 13 years. However, little is known about how children and parents use these activity trackers or perceive their acceptability., Objective: This study primarily aimed to ascertain parental perspectives on the acceptability and usability of wearables designed to monitor children's physical activity levels. Secondary aims were to (1) identify practical considerations for future use in physical activity interventions and promotion initiatives; (2) determine use of different features and functions incorporated into the accompanying app; and (3) identify parents' awareness of their child's current physical activity levels., Methods: In total, 36 children (18 boys and 18 girls) aged 7-12 years were asked to wear a wrist-worn activity tracker (KidFit) for 4 consecutive weeks and to use the accompanying app with parental assistance and guidance. Each week, one parent from each family (n=25; 21 mothers and 4 fathers) completed a Web-based survey to record their child's activity tracker use, app interaction, and overall experiences. At the end of the 4-week period, a subsample of 10 parents (all mothers) participated in face-to-face interviews exploring perceptions of the acceptability and usability of wearable activity trackers and accompanying apps. Quantitative and qualitative data were analyzed descriptively and thematically, respectively. Thematic data are presented using pen profiles, which were constructed from verbatim transcripts., Results: Parents reported that they and their children typically found the associated app easy to use for activity tracking, though only step or distance information was generally accessed and some difficulties interpreting the data were reported. Children were frustrated with not being able to access real-time feedback, as the features and functions were only available through the app, which was typically accessed by, or in the presence of, parents. Parents identified that children wanted additional functions including a visual display to track and self-monitor activity, access to the app for goal setting, and the option of undertaking challenges against schools or significant others. Other barriers to the use of wearable activity trackers included discomfort of wearing the monitor because of the design and the inability to wear for water- or contact-based sports., Conclusions: Most parents reported that the wearable activity tracker was easy for their child or children to use and a useful tool for tracking their children's daily activity. However, several barriers were identified, which may impact sustained use over time; both the functionality and wearability of the activity tracker should therefore be considered. Overall, wearable activity trackers for children have the potential to be integrated into targeted physical activity promotion initiatives., (©Kelly A D Mackintosh, Stephanie E Chappel, Jo Salmon, Anna Timperio, Kylie Ball, Helen Brown, Susie Macfarlane, Nicola D Ridgers. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 04.11.2019.)

Background: Although several studies highlighted an association between occupational exposure and Dupuytren's contracture (DC), they were often limited by the highly selected population. We aimed to study this association using a job-exposure matrix (JEM) and self-reported exposure in a large cohort., Methods: From CONSTANCES, a French population-based prospective cohort, we retrieved sex, age, social position, alcohol/tobacco intake and diabetes. Lifetime exposures were assessed by two different methods: with the biomechanical JEM 'JEM Constances', we assessed exposure to vibration and/or forearm rotation for participants whose work history was available, and from a self-administered questionnaire, we retrieved self-reported exposure to arduous work and/or carrying heavy loads. Surgery for DC was collected from the French Health Administrative database from 2009 to 2016. Multivariate logistic regression models adjusted for confounders were built to assess association between surgery for DC and occupational exposures., Results: Work history was retrieved for 23 795 subjects among whom 98 underwent surgery for DC. Adjusted OR (aOR) was 2.08 (1.03-4.2) for being ever exposed to vibration and/or forearm rotation for subjects <60 years and 1.20 (0.69-2.08) for subjects ≥60 years. Data for self-reported exposure were available for 81 801 participants among whom 367 underwent surgery for DC. aOR for being exposed more than 20 years to arduous work and/or carrying heavy loads was 2.01 (1.32-3.04) for subjects <60 years and 1.04 (0.7-1.54) for subjects ≥60., Conclusions: Manual work is associated with surgery for DC among younger subjects. Monitoring exposed workers is important to prevent future functional limitations., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Mobile health (mHealth) technology takes advantage of smartphone features to turn them into research tools, with the potential to reach a larger section of the population in a cost-effective manner, compared with traditional epidemiological methods. Although mHealth apps have been widely implemented in chronic diseases and psychology, their potential use in the research of vector-borne diseases has not yet been fully exploited., Objective: This study aimed to assess the usability and feasibility of The Tick App, the first tick research-focused app in the United States., Methods: The Tick App was designed as a survey tool to collect data on human behaviors and movements associated with tick exposure while engaging users in tick identification and reporting. It consists of an enrollment survey to identify general risk factors, daily surveys to collect data on human activities and tick encounters (Tick Diaries), a survey to enter the details of tick encounters coupled with tick identification services provided by the research team (Report a Tick), and educational material. Using quantitative and qualitative methods, we evaluated the enrollment strategy (passive vs active), the user profile, location, longitudinal use of its features, and users' feedback., Results: Between May and September 2018, 1468 adult users enrolled in the app. The Tick App users were equally represented across genders and evenly distributed across age groups. Most users owned a pet (65.94%, 962/1459; P<.001), did frequent outdoor activities (recreational or peridomestic; 75.24%, 1094/1454; P<.001 and 64.58%, 941/1457; P<.001, respectively), and lived in the Midwest (56.55%, 824/1457) and Northeast (33.0%, 481/1457) regions in the United States, more specifically in Wisconsin, southern New York, and New Jersey. Users lived more frequently in high-incidence counties for Lyme disease (incidence rate ratio [IRR] 3.5, 95% CI 1.8-7.2; P<.001) and in counties with cases recently increasing (IRR 1.8, 95% CI 1.1-3.2; P=.03). Recurring users (49.25%, 723/1468) had a similar demographic profile to all users but participated in outdoor activities more frequently (80.5%, 575/714; P<.01). The number of Tick Diaries submitted per user (median 2, interquartile range [IQR] 1-11) was higher for older age groups (aged >55 years; IRR 3.4, 95% CI 1.5-7.6; P<.001) and lower in the Northeast (IRR[NE] 0.4, 95% CI 0.3-0.7; P<.001), whereas the number of tick reports (median 1, IQR 1-2) increased with the frequency of outdoor activities (IRR 1.5, 95% CI 1.3-1.8; P<.001)., Conclusions: This assessment allowed us to identify what fraction of the population used The Tick App and how it was used during a pilot phase. This information will be used to improve future iterations of The Tick App and tailor potential tick prevention interventions to the users' characteristics., (©Maria P Fernandez, Gebbiena M. Bron, Pallavi A Kache, Scott R Larson, Adam Maus, David Gustafson Jr, Jean I Tsao, Lyric C Bartholomay, Susan M Paskewitz, Maria A Diuk-Wasser. Originally published in JMIR Mhealth and Uhealth (http://mhealth.jmir.org), 24.10.2019.)

Many new decision aids are developed while aspects of existing decision aids could also be useful, leading to a sub-optimal use of resources. To support treatment decision-making in prostate cancer patients, a pre-existing evidence-based Canadian decision aid was adjusted to Dutch clinical setting. After analyses of the original decision aid and routines in Dutch prostate cancer care, adjustments to the decision aid structure and content were made. Subsequent usability testing (N = 11) resulted in 212 comments. Care providers mainly provided feedback on medical content, and patients commented most on usability and summary layout. All participants reported that the decision aid was comprehensible and well-structured and would recommend decision aid use. After usability testing, final adjustments to the decision aid were made. The presented methods could be useful for cultural adaptation of pre-existing tools into other languages and settings, ensuring optimal usage of previous scientific and practical efforts and allowing for a global, incremental decision aid development process.

The functionality of a workspace is one of the most important considerations in both virtual world design and interior design. To offer appropriate functionality to the user, designers usually take some general rules into account, e.g., general workflow and average stature of users, which are summarized from the population statistics. Yet, such general rules cannot reflect the personal preferences of a single individual, which vary from person to person. In this paper, we intend to optimize a functional workspace according to the personal preferences of the specific individual who will use it. We come up with an approach to learn the individual's personal preferences from his activities while using a virtual version of the workspace via virtual reality devices. Then, we construct a cost function, which incorporates personal preferences, spatial constraints, pose assessments, and visual field. At last, the cost function is optimized to achieve an optimal layout. To evaluate the approach, we experimented with different settings. The results of the user study show that the workspaces updated in this way better fit the users.

The objective of this work is to demonstrate a method for examining the competing effects of secular trends in body size, seat size and configuration, and the increased load factor of aeroplanes. The method uses statistical modelling and virtual fit testing to provide a flexible environment for exploring the impact of various parameters on passenger accommodation. A case study demonstrates the method by exploring the effect of seat width on the accommodation of US civilians (based on seated hip breadth). The case study demonstrates that recent trends of decreasing seat widths and increasing load factors lead to higher disaccommodation. Based on anthropometry and virtual fit, women are also shown to be disproportionately disaccommodated compared to men. Practitioner summary: Airlines are reducing seat width at the same time that individuals worldwide are getting larger. Flights are increasingly crowded, with load factor at a record high. This paper explores the effects of seat width on passenger accommodation under several scenarios involving load factor, demographics, and passenger seating allocation strategies.

Objectives/hypothesis: To evaluate the presence of postural-related strain and musculoskeletal discomfort, along with the level of ergonomics training and the availability of ergonomic equipment among otolaryngology surgeons., Study Design: Intraoperative observations and survey study., Methods: Using the Rapid Entire Body Assessment score system to identify ergonomic hazards, we conducted intraoperative observations assessing operating room personnel during different otolaryngological subspecialty procedures. Based on these findings, otolaryngology surgeons at a single academic institution in the United States were sent a survey that evaluated ergonomic practice, environmental infrastructure, and prior ergonomic training or education., Results: A response rate of 69% was obtained from 70 surgeons, with 72.9% of responding surgeons suffering from some level of back pain, with cervical spine pain being the most common. Interestingly, residents were equally affected when compared to more senior surgeons both in subjective survey reports and from observational risk analysis. Furthermore, 43.8% of surgeons reported suffering from the highest level of pain when standing, whereas only 12.5% experienced pain when sitting. Importantly, 10% stated that pain impacted their work. Only 24% of surgeons had any prior ergonomic training or education., Conclusions: Our data suggest that pain and disability induced by poor ergonomics are widespread among the otolaryngology community and confirm that surgeons rarely receive ergonomic training in the surgical context. Additionally, intraoperative observational findings identified that the majority of observed surgeons display poor posture, particularly a poor cervical angle and use of ergonomic setups, both of which increase ergonomic risk hazard. These data provide guidance for future interventional studies., Level of Evidence: NA Laryngoscope, 129:370-376, 2019., (© 2018 The American Laryngological, Rhinological and Otological Society, Inc.)

Forty-three occupational health professionals (observers) and 90 workers were enrolled in this study to perform the cross-cultural adaptation of the Rapid Office Strain Assessment into Brazilian Portuguese (ROSA-Br) and evaluate its psychometric properties. After cross-cultural adaptation, the measurement properties were checked in three stages: study 1: pre-testing (27 observers rated 15 office worker videos), study 2: intra- and inter-observer reliability (26 observers rated 15 office worker videos), and study 3: validity and accuracy of ROSA-Br final scores (90 office workers). For the ROSA scores, acceptable intraclass correlation coefficients were found for 75% and 86% of the intra-observer reliability comparisons for non-trained and trained observers, respectively, and for 100% of the inter-observer reliability comparisons (0.43-0.86). For construct validity, moderate correlations were observed for 70% of the comparisons between ROSA final scores and other ergonomic instruments. Moderate accuracy was observed for a ROSA-Br final score of 6 (AUC [area under the curve] = 0.72, 0.89). Taken together, these results support the use of the ROSA-Br for ergonomic field assessments and research., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: Federal Region X is an administrative region in the northwestern United States comprised of the states of Alaska (AK), Idaho (ID), Oregon (OR), and Washington (WA). Quantifying the number of workers in this region exposed to harmful circumstances in the workplace, and projected changes over time will help to inform priorities for occupational health training, risk reduction, and research., Methods: State data for WA, ID, OR, and AK were used to estimate number of workers by occupation, in 2014 and 2024. These data were merged with a Canadian job-exposure matrix (CANJEM) which characterizes chemical exposures, and O*NET, which ranks occupations with particular physical, ergonomic, and psychosocial exposures., Results: Of the exposures considered, psychosocial and ergonomic exposures were the most prevalent among the regional workforce, though traditional chemical exposures are still common and increasing., Conclusions: Exposure surveillance will inform prioritization of risk reduction strategies, ultimately leading to a decrease in occupational injury and illness. Findings from this analysis will help to prioritize occupational health training and research in the region., (© 2018 Wiley Periodicals, Inc.)

Background: Construction workers are at greater risk of musculoskeletal disorders due to their exposure to physical ergonomic risk factors., Objectives: The purpose of this study is to quantify the ergonomic hazards for workers in the construction of residential buildings., Methods: In this cross-sectional study, PATH method, a work-sampling observation method, was applied to study the working postures, handled loads, and manual material handling activities in construction workers. A total of 5832 observations were made on 10 workers involved in tasks of three jobs including reinforcing bar, formwork, and pouring concrete. The ergonomic exposure was characterized in terms of percentage of observations made for each task., Results: Non-neutral trunk postures, especially mild and severe flexions, were frequently observed in all job tasks. High-strain leg postures of squatting, kneeling, and leg(s) bent were mostly observed in floor formwork (39%), concrete finishing (5%), and floor rebar construction (52.3%), respectively. The highest proportion of work time with one (5.8%) and two hands (9%) at/above shoulder was observed in column rebar construction. In concrete pouring and rebar cutting, workers were observed in 39.45% and 23.1% of work time doing carry and push/pull activities, respectively. Heavy loads (>15 kg) were mostly observed in concrete pouring and floor formwork tasks., Conclusion: In the construction of residential buildings with the concrete structure, workers perform their task with non-neutral postures of trunk and leg and handling heavy loads. The recommended controls could reduce the musculoskeletal stress in rebar tying, concrete pouring, and concrete finishing tasks.

Research has shown that older adults interact with products less intuitively than younger adults, and that familiarity is an essential element of intuitive interaction. This paper reports on the findings of two empirical studies that examined familiarity in younger and older adults. Each study comprised 32 participants over four age groups. The first study required participants to use their own contemporary products in their homes in order to investigate older adults' familiarity with them, and how this familiarity differed from that of younger adults. Older people were less familiar with their own contemporary products that younger people. The second study aimed to investigate differences in familiarity between younger and older adults while using products that they did not own and were likely to be less familiar with. When using products not already familiar to them, both middle aged and older adults showed significantly lower familiarity than younger people. The significance of this research is in its empirical findings about familiarity differences between age groups. It has been recognised that the identification and understanding of differences in familiarity will enable designers to design more intuitive interfaces and systems for both younger and older cohorts. The implications of the findings from the two studies reported here are discussed in light of this recognition., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The so-called 'fatal five' behaviours (drink and drug driving, distraction and inattention, speeding, fatigue, and failure to wear a seat belt) are known to be the major behavioural contributory factors to road trauma. However, little is known about the factors that lead to drivers engaging in each behaviour. This article presents the findings from a study which collected and analysed data on the factors that lead to drivers engaging in each behaviour. The study involved a survey of drivers' perceptions of the causes of each behaviour and a subject matter expert workshop to gain the views of road safety experts. The results were mapped onto a systems ergonomics model of the road transport system in Queensland, Australia, to show where in the system the factors reside. In addition to well-known factors relating to drivers' knowledge, experience and personality, additional factors at the higher levels of the road transport system related to road safety policy, transport system design, road rules and regulations, and societal issues were identified. It is concluded that the fatal five behaviours have a web of interacting contributory factors underpinning them and are systems problems rather than driver-centric problems. The implications for road safety interventions are discussed., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Seat effective amplitude transmissibilities (SEAT values) quantify the influence of seats on discomfort caused by vibration. This study investigated SEAT values with vertical mechanical shocks at low, medium, and high magnitudes (0.5, 1.0, and 2.0 ms -1.75 ) at frequencies between 1.0 and 16 Hz. With 18 subjects sitting on a rigid seat and two foam cushions, SEAT values were measured objectively (from the transmitted vibration), measured subjectively (by the responses of subjects), and predicted (using a model of the seat-passenger system). Except with high magnitude low frequency shocks, predicted SEAT values were similar to measured SEAT values. With shocks causing subjects to rise off a cushion and subsequently impact the cushion (low frequencies around 1 g), subjective SEAT values were better estimated using predicted SEAT values than objectively measured SEAT values, because accelerometers on cushions exaggerated the impact of the falling subject. However, accelerometers on rigid seats will underestimate such impacts., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Purpose of Review: Work-related musculoskeletal disorders (WMSDs) are prevalent among surgeons and result in significant disability. We aimed to review the English-language literature regarding ergonomic risk, prevalence of WMSDs, and unique ergonomic considerations of gynecologic surgery., Recent Findings: Surgeon WMSDs are prevalent, with rates ranging from 66 to 94% for open surgery, 73-100% for conventional laparoscopy, 54-87% for vaginal surgery, and 23-80% for robotic-assisted surgery. Risk factors for injury in open surgery include use of loupes, headlamps, and microscopes. Unique risks in laparoscopic surgery include table and monitor position, long-shafted instruments, and poor instrument handle design. In vaginal surgery, improper table height and twisted trunk position create injury risk. Although robotic surgery offers some advantages in neck and shoulder strain, it remains associated with trunk, wrist, and finger strain., Summary: WMSDs are prevalent among surgeons but have received little attention because of under-reporting of injury and logistical constraints of studying surgical ergonomics. Future research must aim to develop objective surgical ergonomics instruments and guidelines and to correlate ergonomics assessments with pain and tissue-level damage in surgeons with WMSDs. Ergonomics training should be developed and implemented in order to protect surgeons from preventable, potentially career-altering injuries.

Background:  To date, no review has been conducted on the growing body of literature describing various work-related musculoskeletal disorders (MSDs), ergonomic hazards, and potential interventions relevant to plastic surgeons. This systematic review sought to (1) define the scope of coverage of this important issue in the peer-reviewed literature; (2) critically assess the evidence; and (3) provide recommendations for future directions., Methods:  We conducted a literature search of MEDLINE, Embase, Web of Science, and PubMed from the inception of each database until 2016. All articles reporting on work-related MSDs or ergonomics among plastic surgeons were reviewed, summarized, and assessed for trends., Results:  Sixteen articles met our inclusion criteria including five expert opinions, four cross-sectional studies and case reports/series, one review, and six experimental studies. Four articles presented evidence on disease burden. The most commonly described work-related MSD was cervical spine disease, for which one study reported a career prevalence of 24.7% (point prevalence in the general population: 0.1-0.4%); three studies reported 64 cases of surgeon work-related MSD resulting in surgical intervention, decreased productivity, or involuntary early retirement. Eight studies described interventions, most of which aimed to improve the ergonomics of microsurgery., Conclusion:  This review found low-level evidence of plastic surgeons' vulnerability to a work-related MSD at times severe enough to end careers. Further investigation is needed to clearly define this important problem in plastic surgery. Specifically, future directions should include more methodologically rigorous epidemiologic studies evaluating disease burden., Competing Interests: None., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Introduction: The effect of different kinds of work on the psychosocial assessment of workers under the same management and organizational environment is investigated., Methods: A voluntary assessment in a utility company was carried out using the short version of the Copenhagen psychosocial questionnaire (CoPsoQ) on two occasions, 1.5 years apart. Initially, 25 office workers (11 men and 14 women) participated, while 14 of those workers (8 women and 6 men) participated in the second assessment together with 32 field workers. The sewage, water treatment and maintenance workers, totaling 32 men, also participated in a field ergonomics assessment using the Washington State Department of Labor and Industries field work ergonomic checklist., Results: The longitudinal outlook was fairly stable, with sustained severe scores in many CoPsoQ subscales and intensification of severity of workers' control over work and esteem for men. A significantly higher esteem score resulted for field rather than office workers. Workers subjected to foul odors showed similar severity of psychosocial factors., Discussion: For most psychosocial dimensions, the organizational design and management system in place, as well as the overall cultural environment in which it operates, create a much stronger and more decisive impact than job-specific factors.

Objective: To gather information on the (a) types of wearable sensors, particularly personal activity monitors, currently used by occupational safety and health (OSH) professionals; (b) potential benefits of using such technologies in the workplace; and (c) perceived barriers preventing the widespread adoption of wearable sensors in industry., Background: Wearable sensors are increasingly being promoted as a means to improve employee health and well-being, and there is mounting evidence supporting their use as exposure assessment and personal health tools. Despite this, many workplaces have been hesitant to adopt these technologies., Methods: An electronic survey was emailed to 28,428 registered members of the American Society of Safety Engineers (ASSE) and 1,302 professionals certified by the Board of Certification in Professional Ergonomics (BCPE)., Results: A total of 952 valid responses were returned. Over half of respondents described being in favor of using wearable sensors to track OSH-related risk factors and relevant exposure metrics at their respective workplaces. However, barriers including concerns regarding employee privacy/confidentiality of collected data, employee compliance, sensor durability, the cost/benefit ratio of using wearables, and good manufacturing practice requirements were described as challenges precluding adoption., Conclusion: The broad adoption of wearable technologies appears to depend largely on the scientific community's ability to successfully address the identified barriers., Application: Investigators may use the information provided to develop research studies that better address OSH practitioner concerns and help technology developers operationalize wearable sensors to improve employee health and well-being.

Objective The objective of this paper is to examine quotation error in human factors. Background Science progresses through building on the work of previous research. This requires accurate quotation. Quotation error has a number of adverse consequences: loss of credibility, loss of confidence in the journal, and a flawed basis for academic debate and scientific progress. Quotation error has been observed in a number of domains, including marine biology and medicine, but there has been little or no previous study of this form of error in human factors, a domain that specializes in the causes and management of error. Methods A study was conducted examining quotation accuracy of 187 extracts from 118 published articles that cited a control article (Vaughan's 1996 book: The Challenger Launch Decision: Risky Technology, Culture, and Deviance at NASA). Results Of extracts studied, 12.8% ( n = 24) were classed as inaccurate, with 87.2% ( n = 163) being classed as accurate. A second dimension of agreement was examined with 96.3% ( n = 180) agreeing with the control article and only 3.7% ( n = 7) disagreeing. The categories of accuracy and agreement form a two by two matrix. Conclusion Rather than simply blaming individuals for quotation error, systemic factors should also be considered. Vaughan's theory, normalization of deviance, is one systemic theory that can account for quotation error. Application Quotation error is occurring in human factors and should receive more attention. According to Vaughan's theory, the normal everyday systems that promote scholarship may also allow mistakes, mishaps, and quotation error to occur.

Background: The anaesthesia ventilator represents the key equipment for intraoperative respiratory care. Improper operation of this device may threaten a patient's health. A self-explanatory interface facilitates handling and decreases the risk of operating errors. This study systematically evaluates the usability of user interfaces in four modern anaesthesia ventilators., Methods: Twenty naïve operators were asked to execute 20 tasks on each of four different anaesthesia ventilators (Avance CS2™, GE Healthcare; Flow-i™, Maquet; and Perseus™ and Primus™, Dräger) in a randomized order. The success of task execution, frequency of requests for assistance, and processing times were recorded. During the tasks, the operators' visual focus was measured via eye-tracking. Additionally, subjective assessments of usability were evaluated by a standardized questionnaire. For comparison, six experienced operators undertook the same protocol., Results: The overall rate of falsely executed tasks was low. Naïve operators requested assistance least when using the Perseus (26). Pooled processing times were shortest for the Perseus (222 s), followed by the Primus (223 s), the Avance (238 s), and the Flow-i (353 s). Task-specific processing times differed considerably between the devices. Eye-tracking analyses revealed associated interface issues that impeded the operators' performance. Operators rated usability best for the Perseus [mean (sd): 67 (17) arbitrary units] and worst for the Flow-i [50 (16) arbitrary units]. Results from experienced operators support these findings by trend., Conclusions: The usability of modern anaesthesia ventilators differs considerably. Interface issues of specific tasks impair the operator's efficiency. Eliminating the specific usability issues might improve the operator's performance and, as a consequence, the patient's safety., (© The Author 2017. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com)

Background: Posture, vision, and instrumentation limitations are the main predicaments of conventional laparoscopy., Objective: To combine the ETHOS surgical chair, the three-dimensional laparoscope, and the Radius Surgical System manipulators, and compare the system with conventional laparoscopy and da Vinci in terms of task completion times and discomfort., Design, Setting, and Participants: Fifteen trainees performed the three main laparoscopic suturing tasks of the Heilbronn training program (IV: simulation of dorsal venous complex suturing; V: circular suturing of tubular structure; and VI: urethrovesical anastomosis) in a pelvi trainer. The tasks were performed conventionally, utilizing the three devices, and robotically. Task completion times were recorded and the surgeon discomfort was evaluated using questionnaires., Outcome Measurements and Statistical Analysis: Task completion times were compared using nonparametric Wilcoxon signed rank test and ergonomic scores were compared using Pearson chi-square test., Results and Limitations: The use of the full laparoscopic set (ETHOS chair, three-dimensional laparoscopic camera, Radius Surgical System needle holders), resulted in a significant improvement of the completion time of the three tested tasks compared with conventional laparoscopy (p<0.001) and similar to da Vinci surgery. After completing Tasks IV, V, and VI conventionally, 12 (80%), 13 (86.7%), and 13 (86.7%) of the 15 trainees, respectively, reported heavy total discomfort. The full laparoscopic system nullified heavy discomfort for Tasks IV and V and minimized it (6.7%) for the most demanding Task VI. Especially for Task VI, all trainees gained benefit, by using the system, in terms of task completion times and discomfort. The limited trainee robotic experience and the questionnaire subjectivity could be a potential limitation., Conclusions: The ergonomic laparoscopic system offers significantly improved task completion times and ergonomy than conventional laparoscopy. Furthermore, it demonstrates comparable results to robotic surgery., Patient Summary: The study was conducted in a pelvi trainer and no patients were recruited., (Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.)

We evaluated the impact of a workplace 'sit less, move more' programme (Walk@WorkSpain, W@WS, 19-week) on self-reported activity-related energy expenditure (AREE) in Spanish office employees (n = 264; 42 ± 10 years; 171 female) randomly assigned to Intervention (IG; used W@WS; n = 129) or comparison groups (CGs; n = 135). A linear mixed model assessed changes in METs-min/wk of total, vigorous, moderate and light physical activity (IPAQ short form) between baseline and 2 months follow-up. Over the CG, IG significantly increased light intensity AREE (P = 0.027). W@WS secured sustained increases on AREE-but not on achieving PA recommendations-providing translational evidence that active living in office employees can be increased., (© The Author 2017. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.)

Background: Low back pain (LBP) is the most common form of work-related musculoskeletal disorders, which cause huge economic losses to individuals as well as to the community. Bus drivers have been found to be at an increased risk of LBP owing to several factors associated with physical and occupational circumstances. There is scant knowledge on the problems of LBP among bus drivers in Egypt., Aim: To identify the prevalence of LBP among bus drivers and to determine the ergonomic and occupational risk factors associated with this problem., Materials and Methods: This is a cross-sectional study including 180 public bus drivers who were interviewed using a questionnaire containing items on some sociodemographic, ergonomic, and occupational characteristics. Lifestyle risk factors such as BMI and history of tobacco smoking were also included in the questionnaire., Results: The prevalence of LBP was high (73.9%). LBP was significantly associated with work duration of more than 10 years, working more than 8 h/day and more number of accidents while driving the bus in the previous year. Regarding ergonomic risk factors, those complaining of uncomfortable seat and steering wheels showed significantly higher prevalence of LBP., Conclusion: Public bus drivers in this study experienced high prevalence of LBP, which was associated with long duration of work, driving for more than 8 h daily and uncomfortable seat and steering wheels. Ergonomic and occupational risk factors associated with LBP can be modified by proper organizational strategies and health plans. Therefore, assessment of the sitting biomechanics and regular maintenance of buses are recommended to prevent any adverse health effects.

The reliability of the Human Factors Analysis and Classification System (HFACS) for classifying retrospective observational human factors data in the cardiovascular operating room is examined. Three trained analysts independently used HFACS to categorize observational human factors data collected at a teaching and nonteaching hospital system. Results revealed that the framework was substantially reliable overall (Study I: k = 0.635; Study II: k = 0.642). Reliability increased when only preconditions for unsafe acts were investigated (Study I: k =0.660; Study II: k = 0.726). Preconditions for unsafe acts were the most commonly identified issues, with HFACS categories being similarly populated across both hospitals. HFACS is a reliable tool for systematically categorizing observational data of human factors issues in the operating room. Findings have implications for the development of a HFACS tool for proactively collecting observational human factors data, eliminating the necessity for classification post hoc.

Evaluating physical discomfort of designed gestures is important for creating safe and usable gesture-based interaction systems; yet, gestural discomfort evaluation has not been extensively studied in HCI, and few evaluation methods seem currently available whose utility has been experimentally confirmed. To address this, this study empirically demonstrated the utility of the subjective rating method after a small number of gesture repetitions (a maximum of four repetitions) in evaluating designed gestures in terms of physical discomfort resulting from prolonged, repetitive gesture use. The subjective rating method has been widely used in previous gesture studies but without empirical evidence on its utility. This study also proposed a gesture discomfort evaluation method based on an existing ergonomics posture evaluation tool (Rapid Upper Limb Assessment) and demonstrated its utility in evaluating designed gestures in terms of physical discomfort resulting from prolonged, repetitive gesture use. Rapid Upper Limb Assessment is an ergonomics postural analysis tool that quantifies the work-related musculoskeletal disorders risks for manual tasks, and has been hypothesized to be capable of correctly determining discomfort resulting from prolonged, repetitive gesture use. The two methods were evaluated through comparisons against a baseline method involving discomfort rating after actual prolonged, repetitive gesture use. Correlation analyses indicated that both methods were in good agreement with the baseline. The methods proposed in this study seem useful for predicting discomfort resulting from prolonged, repetitive gesture use, and are expected to help interaction designers create safe and usable gesture-based interaction systems.

Background: More than 90% of the elementary school students in the world and most of the Iranian students use backpacks. Heavy school bags, failure to apply ergonomics standards in student's backpacks, and also mismatch between anthropometrics dimensions and schoolbag size are important issues for children's health., Objective: The purpose of this study was to gather baseline information on the average weight carried by female primary students. It also aimed to evaluate ergonomics standards for student backpacks., Methods: A cross-sectional study was conducted on 212 Iranian girl students aged 6- 11 years. Body weight and bag weight were measured with electronic scales and body mass index calculated with WHO software 2007. A questionnaire was constructed to gather information about the backpacks. Body dimensions were measured with VICON motion Analyze system (460). Ergonomics factors were recorded using a checklist., Results: 80.8% of the students used a backpack at a higher weight than recommended by the standards of 10% of body weight. The most common type of schoolbag used was double strap packs (92.5%). The majority of the students carried packs on their backs; however, most of them did not make any adjustments (79.8%). The results have shown a mismatch between the anthropometric measures and the student's backpack dimensions., Conclusions: Parents, students and school staff should be informed about these critical issues as well as suitable controls should be implemented in buying and using the bags.

The number of fatal occupational injuries (FOI), the number of scientific publications in ergonomics (SP) and the gross domestic product (GDP) of 30 countries were investigated for their mutual dependence. This article shows that, although the ratio of FOI/SP decreases exponentially with a linear increase in the GDP, GDP may be only one of the major influencing factors.

Introduction: Despite the increasingly widespread popularity of electronic devices, there are limited comprehensive studies on the effects of usage and exposure to multiple electronic devices over extended periods of time. Therefore, this study explored the cumulative musculoskeletal implications of exposure to various electronic devices among university students., Methods: A self-reported questionnaire was administered in the university in Hong Kong and students provided information about the frequency and duration of electronic devices use, including computers, mobile phones and game consoles, and reported on any musculoskeletal pain or discomfort that may relate to electronic devices usage in the immediate 12 months prior to the survey date., Results: A total of 503 university students (59% males and 41% females) aged 18-25 years completed the questionnaire. The results showed that 251 (49.9%) respondents reported upper limb musculoskeletal symptoms, particularly in the neck and shoulder regions. Among these, 155 (61.8%) indicated that their discomfort was related to electronic device usage. Statistically significant differences in exposure to electronic devices and musculoskeletal outcomes between genders were found (p < 0.05)., Conclusion: The use of electronic devices and habitual postures were associated with musculoskeletal problems among university students in Hong Kong. This phenomenon highlights the urgent need for ergonomics education and recommendations to increase students' awareness of musculoskeletal wellbeing., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the ease of handling of two rebound tonometers, which are designed for self-measurement of intraocular pressure (IOP) in a clinical setting by untrained patients., Methods: After self-measurement of the IOP with the rebound tonometers iCare ONE and iCare HOME, participants were asked to complete a questionnaire containing different subitems concerning ease of operation using a visual analog scale (1 = very good to 5 = very poor). Moreover, the feasibility and duration of measurement were tested., Results: A total of 147 subjects participated in this study. The mean score for general handling ability was 2.79 ± 1.01 for the iCare ONE and 1.85 ± 0.87 for the iCare HOME (p < 0.001). The evaluation of the subitems sense of safety (iCare ONE: 2.71 ± 1.03 and iCare HOME: 1.87 ± 0.81, p < 0.001) and comfort of measurement (iCare ONE: 2.07 ± 1.01 and iCare HOME: 1.66 ± 0.72, p < 0.001) also showed a significant discrepancy between the two tonometers. Participants needed significantly less time for a single valid measurement when using the iCare HOME tonometer (mean 66.14 ± 61.54 s) compared to the iCare ONE tonometer (mean 81.54 ± 69.51 s, p < 0.001)., Conclusions: A better handling of the iCare HOME rebound tonometer in comparison to the iCare ONE tonometer can be deduced on the basis of the subjective assessments of patients and the shorter duration of measurements. Moreover, the iCare HOME received a significantly better evaluation for all subitems. The accuracy of measurements using the iCare HOME still needs to be clarified.

Background: As technology infiltrates more of our personal and professional lives, user expectations for intuitive design have driven many consumer products, while medical equipment continues to have high training requirements. Not much is known about the usability and user experience associated with hospital monitoring equipment. This pilot project aimed to better understand and describe the user interface interaction and user experience with physiologic monitoring technology., Design: This was a prospective, descriptive, mixed-methods quality improvement project to analyze perceptions and task analyses of physiologic monitors., Methods: Following a survey of practice patterns and perceived abilities to accomplish key tasks, 10 voluntary experienced physician and nurse subjects were asked to perform a series of tasks in 7 domains of monitor operations on GE Monitoring equipment in a single institution. For each task analysis, data were collected on time to complete the task, the number of button pushes or clicks required to accomplish the task, economy of motion, and observed errors., Results: Although 60% of the participants reported incorporating monitoring data into patient care, 80% of participants preferred to receive monitoring data at the point of care (bedside). Average perceived central station usability is 5.3 out of 10 (ten is easiest)., Conclusions: High variability exists in monitoring station interaction performance among those participating in this project. Alarms were almost universally silenced without cognitive recognition of the alarm state. Education related to monitoring operations appeared largely absent in this sample. Most users perceived the interface to not be intuitive, complaining of multiple layers and steps for data retrieval. These clinicians report real-time monitoring helpful for abrupt changes in condition like arrhythmias; however, reviewing alarms is not prioritized as valuable due to frequent false alarms. Participants requested exporting monitoring data to electronic medical records. Much research is needed to develop best practices for display of real-time information, organization and filtering of meaningful data, and simplified ways to find information., (Published by Elsevier Inc.)

Objectives: Physical exposures (eg, lifting or bending) are believed to be risk factors for low-back pain (LBP), but the literature is inconsistent. Exposure and LBP prevalence differ considerably between occupations, and exposure-outcome associations could be severely modified by the presence of particular occupational groups. We aimed to investigate the influence of such outlying groups on the properties of associations between exposure and LBP., Methods: Lifting and trunk flexion were observed for 371 of 1131 workers within 19 groups. LBP was obtained from all workers during three follow-up years. Both exposure variables were associated with LBP (P<0.01) in this parent dataset. By removing the 19 groups one-by-one and performing logistic regressions analysis on the 18 remaining groups, we demonstrated that one group, mainly road workers, with outlying exposures and LBP prevalence substantially affected the exposure-outcome association in the total population. In order to further examine this phenomenon, we assessed, by simulation, the influence of realistic sizes (n=4, 8, 16, 32, 64, 128), mean exposures (e=2000, 3000, 4000 lifts and e=30, 40, 50% trunk flexion time) and LBP prevalences (p=70, 80, 90, 100%) of the outlying group on the strength and certainty of the eventual relationship between exposure and LBP. For each combination of n, e and p, 3000 virtual studies were constructed, including the simulated group together with the other 18 original groups from the parent data-set. Average odds ratios (OR), 95% confidence limits, and power (P<0.05) were calculated across these 3000 studies as measures of the properties of each virtual study design., Results: OR were attenuated more towards 1 and power decreased with smaller values of n, e, and p in the outlying group. Changes in group size and prevalence had a larger influence on OR and power than changes in mean exposure., Conclusions: The size and characteristics of a single group with high exposure and outcome prevalence can strongly influence both the OR point estimate and the likelihood of obtaining significant exposure-outcome associations in studies of large populations. These findings can guide interpretations of prior epidemiological studies and support informed design of future studies.

Objectives: To determine the activity of the upper trapezius, serratus anterior, anterior deltoid, biceps brachii. and lower trapezius muscles in healthy adults during below-the-knee assembly work., Methods: Fifteen right-handed male subjects participated in this study. The electrical activities, measured by EMG, of the right upper trapezius, serratus anterior, anterior deltoid, biceps brachii. and lower trapezius were measured during below-the-knee assembly work at four workstations of varying height and distance from the participant (workstation 1, below-the-knee assembly work with a height of 15 cm above the floor and a reach distance of 30 cm; workstation 2, height of 15 cm and distance of 45 cm; workstation 3, height of 30 cm and distance of 30 cm; workstation 4, height of 30 cm and distance of 45 cm). Muscle activity at the four workstations was represented as a percentage of the reference voluntary isometric contraction (RVIC)., Results: Height: Upper and lower trapezius activity increased significantly during below the knee assembly work as height above the floor increased. The activities of the serratus anterior and biceps brachii muscles increased significantly during low-height below-the-knee assembly work. Distance: The activities of the upper trapezius, serratus anterior, anterior deltoid and biceps brachii increased significantly during below-the-knee assembly work at a far distance (45 cm). The lower trapezius muscle activity increased significantly during below-the-knee assembly work at a close distance (30 cm)., Conclusions: Below-knee workers should engage in work close to themselves, since distance appears to be a stronger risk factor for injury than height above the floor.

Approximately 33% of stroke patients have difficulty performing activities of daily living, often committing errors during the planning and execution of such activities. The objective of this study was to evaluate the ability of the human error identification (HEI) technique SHERPA (Systematic Human Error Reduction and Prediction Approach) to predict errors during the performance of daily activities in stroke patients with left and right hemisphere lesions. Using SHERPA we successfully predicted 36 of the 38 observed errors, with analysis indicating that the proportion of predicted and observed errors was similar for all sub-tasks and severity levels. HEI results were used to develop compensatory cognitive strategies that clinicians could employ to reduce or prevent errors from occurring. This study provides evidence for the reliability and validity of SHERPA in the design of cognitive rehabilitation strategies in stroke populations.

This study hypothesized that in a longitudinal setting deteriorating physical working conditions increases the perceived physical and mental strain among food processing employees. The study was conducted in 2003 and 2007. It examined 248 blue-collar workers, all of whom were in the same occupation throughout the entire follow-up period. The data were obtained through a structural questionnaire distributed to the employees at the workplace. Mental strain had increased (7%) significantly among younger employees during the follow-up. The changes in mental strain for the younger employees were positively associated with the changes in physical strain. The changes in physical strain were also significantly associated with the changes in physical working conditions among both younger and the older workers. The results of this study partly support the study hypothesis, namely that deteriorating physical working condition increases physical strain and also increases mental strain, especially among younger employees., (Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.)

In industrially developing countries (IDC), small and medium enterprises (SMEs) account for the highest proprotion of employment. Unfortunately, the working conditions in SMEs are often very poor and expose employees to a potentially wide range of health and safety risks. This paper presents a comprehensive review of 161 articles related to ergonomics application in SMEs, using Indonesia as a case study. The aim of this paper is to investigate the extent of ergonomics application and identify areas that can be improved to promote effective ergonomics for SMEs in IDC. The most urgent issue found is the need for adopting participatory approach in contrast to the commonly implemented top-down approach. Some good practices in ergonomics application were also revealed from the review, e.g. a multidisciplinary approach, unsophisticated and low-cost solutions, and recognising the importance of productivity. The review also found that more work is still required to achieve appropriate cross-cultural adaptation of ergonomics application.

Introduction: Computer vision syndrome (CVS) is a condition in which a person experiences one or more of eye symptoms as a result of prolonged working on a computer., Objectives: To determine the prevalence of CVS symptoms, knowledge and practices of computer use in students studying in different universities in Malaysia, and to evaluate the association of various factors in computer use with the occurrence of symptoms., Material and Methods: In a cross sectional, questionnaire survey study, data was collected in college students regarding the demography, use of spectacles, duration of daily continuous use of computer, symptoms of CVS, preventive measures taken to reduce the symptoms, use of radiation filter on the computer screen, and lighting in the room., Results: A total of 795 students, aged between 18 and 25 years, from five universities in Malaysia were surveyed. The prevalence of symptoms of CVS (one or more) was found to be 89.9%; the most disturbing symptom was headache (19.7%) followed by eye strain (16.4%). Students who used computer for more than 2 hours per day experienced significantly more symptoms of CVS (p=0.0001). Looking at far objects in-between the work was significantly (p=0.0008) associated with less frequency of CVS symptoms. The use of radiation filter on the screen (p=0.6777) did not help in reducing the CVS symptoms., Conclusion: Ninety percent of university students in Malaysia experienced symptoms related to CVS, which was seen more often in those who used computer for more than 2 hours continuously per day., (© NEPjOPH.)

Study Design: Descriptive study., Objective: The objective of this study was to present anthropometric data from high school students in Cape Metropole area, Western Cape, South Africa that are relevant for chair design and whether the dimensions of computer laboratory chairs currently used in high schools match linear anthropometrics of high-school students. Summary of Background Data. Learner-chair mismatch is proposed as a cause of poor postural alignment and spinal pain in adolescents. A learner-chair mismatch is defined as the incompatibility between the dimensions of a chair and the anthropometric dimensions of the learner. Currently, there is no published research to ascertain whether the furniture dimensions in school computer laboratories match the anthropometrics of the students. This may contribute to the high prevalence of adolescent spinal pain., Methods: The sample consisted of 689 learners, 13-18 years old. The following body dimensions were measured: stature, popliteal height, buttock-to-popliteal length and hip width. These measurements were matched with the corresponding chair seat dimensions: height, depth and width. Popliteal and seat height mismatch was defined when the seat height is either >95% or <88% of the popliteal height. Buttock-popliteal length and seat depth mismatch was defined when the seat depth is either >95% or <80% of the buttock-popliteal length. Seat width mismatch is defined where the seat width should be at least 10% and at the most 30% larger than hip width., Results: An 89% of learners did not match the seat. Five percent of learners matched the chair depth, the majority was found to be too big. In contrast, 65% of the learners matched the chair width dimension., Conclusions: A substantial mismatch was found. The school chairs failed standard ergonomics recommendations for the design of furniture to fit the user. This study supports the conclusion that there is no one-size-fits-all solution. There is an urgent need for chairs that are of different sizes or that are adjustable., (Copyright © 2012 Elsevier Ltd and The Ergonomics Society. All rights reserved.)

Objective: Musculoskeletal disorders (MSDs) are commonly experienced in dentistry. The objective of this study is to determine the prevalence of ergonomics and MSDs among dental professionals., Materials and Methods: A cross-sectional survey was conducted among 170 dentists of different specialties. The questionnaire gathered information regarding demographic details, MSDs, work duration, working status, awareness of ergonomics, etc. Data was analyzed using SPSS version 15.0. Student's t-test and analysis of variance (ANOVA) test was used for comparison in mean scores. Stepwise multiple linear regression analysis was used to assess the independent variables that significantly influenced the variance in the dependent variable (pain)., Results: It was found that 73.9% of the participants reported musculoskeletal pain and most common painful sites were neck and back. More than half of the participants, i.e. 232 (59.3%) were aware of correct ergonomic posture regarding dental. Almost percentage of pain increased significantly with increase in age and working time. Among all specialties, prosthodontics were found to have more prevalence of MSDs., Clinical Significance: The appearance of musculoskeletal symptoms among dental professionals was quite common. It suggested that ergonomics should be covered in the educational system to reduce risks to dental practitioners.

To reduce the risk of application error, the federal legislator has demanded a development process which is oriented towards usability (DIN EN 62366). Therefore, the research question concerns the application of this standard by medical device manufacturers. Questionnaires were filled out by five trained interviewers in fully standardized face-to-face interviews at MEDICA Düsseldorf 2010. The results are based on 65 interviews. Almost all companies evaluated usability as relevant for product development; however, the understanding of usability through companies can still be improved as well as increasing the amount of trained usability experts in the process.