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Introduction: In this interventional study, the ergonomic workplace set‐up and the impact of character size on subjectively estimated working productivity and computer vision syndrome (CVS) were evaluated in the field. Methods: The number of displays and their size, resolution, surface structure, position in the room and relation to the eye were evaluated for 152 units. CVS was assessed using the CVS‐Questionnaire. Habitually used character size for an uppercase E was recorded and compared to the ISO 9241–303:2011, national standards (e.g., ANSI/HFES 100–2007) and national guidelines (e.g., German DGUV Information 215–410). In case of failure to comply with these standards, character size was increased to 22 angular minutes to reach the recommended ranges. Reasons for returning to former or smaller character sizes were recorded, and subjectively perceived changes in productivity were estimated by the participants using a visual analogue scale before and 2 weeks after the intervention using a questionnaire. Results: The average visual display unit consisted of two non‐glare (matt) 24″ widescreen monitors that were located approximately 73 cm (primary) and 76 cm (secondary) from the eyes. The mean (SD) habitually set character size was 14.29 angular minutes (3.53) and therefore both statistically and clinically significantly too small compared with ISO 9241–303:2011 (p < 0.001). Increasing the character size to 22 angular minutes produced a 26% reduction in subjectively rated productivity (p < 0.001). No significant correlation between character size and symptoms of CVS was demonstrated. Conclusions: In the workplaces investigated, recommendations for character size were not adhered to. This resulted in a reduction in productivity and was not compatible with some of the work requirements, for example, obtaining a broad overview of a spreadsheet. [ABSTRACT FROM AUTHOR]

The purpose of this study was to model the visual ergonomic factors affecting performance in human–computer interaction. A cross-sectional study using structural equation modelling was performed with a sample of 200 participants. The measuring instruments included the office lighting survey questionnaire, performance assessment questionnaires, visual ergonomics assessment and an eye discomfort assessment. The hypothetical model evaluated workplace lighting status and visual ergonomics as precursors, performance as the output and eye discomfort as a mediator. The results showed that eye discomfort directly affected performance. Visual ergonomics also had a significant direct effect on eye discomfort. The final model suggested a significant new path between the quality of lighting and visual ergonomics. Also, the quality of lighting had an indirect effect on eye discomfort and performance, and the effect of visual ergonomics on performance was the same. Improving the lighting quality and visual ergonomics can reduce eye discomfort and increase performance. [ABSTRACT FROM AUTHOR]

Colorblindness is a condition in which the person affected is unable to identify a particular shade of color when it comes in contact with another shade of color in adverse lighting conditions, causing confusion in visual interfaces. Visual experiences on a computer interface consist of many data such as infographics, images, videos, graphs, presentation, maps, diagram, games, etc. Anything that has any kind of color-coded information is affected by color blindness. So, when a colorblind person is exposed to these colors and some conflicting colors are used in these elements, he/she may miss critical information. The graphical user interface (GUI) was introduced to quickly allow users to learn about the essential features of an operating system, thereby increasing productivity. With the evolution of GUI, software manufacturers started developing and including accessibility features in operating systems to cater to the extreme or benchmark users. However, there is still a lot of scope for improvement in the area of color blindness in a computer interface. This article intends to study the problems that occur/may occur for colorblind users with an objective to come up with better design solution to include colorblind users as mainstream user category in a computer interface and expand the user base of existing operating systems. [ABSTRACT FROM AUTHOR]

BACKGROUND: The coronavirus 2019 (COVID-19) pandemic has brought about change in the work environment, increasing remote and hybrid mode of work, presenting a compelling need to study visual ergonomics in this new work environment. OBJECTIVE: To assess computer vision symptoms and visual ergonomics in remote and hybrid work settings during the COVID-19 pandemic with a focus on eye to screen relationship. METHODS: The computer-vision symptom scale (CVSS17) questionnaire and questions about human factors and ergonomics were included in the survey conducted in September 2021. Sixty-six working professionals (mean age 37 years±5), working from home (n = 44) or in hybrid mode (n = 22) were included in the study. Cramer's V was used for the correlation coefficient between two categorical variables for assessing eye health in changing work environments. RESULTS: Compared to our previous study, the correlation between computer vision syndrome (CVS) symptoms is markedly higher. The population working in hybrid mode experienced eye heaviness with strain to see well (V = 0.6872, p = 0.002) and dryness in the eyes (V = 0.5912, p = 0.0179). The population working from home who are bothered by surrounding lights also report dryness in the eyes (V = 0.3846, p = 0.0005). Screen use hours are higher in work from home situations (43% work more than 9 hrs) than those in hybrid mode of work (4% work more than 9 hrs). CONCLUSION: A definite increase in CVS in most of the population working remotely or in hybrid environments is established through this study. User-friendly strategies for raising awareness of applied visual ergonomics can prevent rampant onset of CVS in the working population. [ABSTRACT FROM AUTHOR]

Objectives: To validate and to determine the reliability of the computer vision syndrome questionnaire (CVS-Q) for the evaluation of the informatic visual syndrome in health care personnel in Lina. Methods: cross-sectional study carried-out in 82 health care workers. The validity of the instrument was evaluated by expert evaluation using the Aiken's V statistical method; construct validity was evaluated by factorial analysis; discriminant validity by the operator-receptor curve (ORC) contrasted with CSSV17 questionnaire; internal consistency by Cronbach's alpha and Spearman's Rho and intraclass coefficient correlation with 95% CI to evaluate test and r-test reliability. SPSS version 2.0 for Windows was used to process data. Results: Aiken's V obtained 100%; factorial analysis found 3 components that explained 69.455% of total variance. The ORC area was 0.889 [(0.845-0.934); IC=0.95] (p=0.000), sensitivity 72.22% and specificity of 100%. Cronbach's alpha was 0.939, Rho de Spearman 0.884 (p=0.000) and CCI 0.856 [(0.777 -- 0.907); IC=0.95] (p=0.000). Conclusions: The CVS&lowbar;Q is valid and reliable to be used in health care workers with good psychometric properties. [ABSTRACT FROM AUTHOR]

Objectives. Nearly 60 million people suffer from computer vision syndrome (CVS) globally, resulting in reduced work productivity. This study aimed to determine the prevalence of CVS, describe the working conditions, visualize ergonomic factors and determine preventive measures application among university staff members. Methods. A cross-sectional study was conducted with university medical staff members using a semi-structured questionnaire that included a validated CVS questionnaire. Results. CVS prevalence was 81.2%. Dryness, headache, feeling that sight is worsening and difficulty in focusing on near vision were the most experienced symptoms. Prevalence of CVS was significantly higher among females (52.3%), those having a higher mean work duration (21.65 ± 7.55 years), those who frequently use a smartphone (84.9%) and those spending most of their screen time during both day and night (87.1%). Visual ergonomics and preventive measures application, such as correct screen level, regular cleaning of the screen, appropriate illumination and use of eye drops, were significantly associated with negative CVS. Conclusions. These results raised attention to the essential need for visual assessment of university staff members for early and proper diagnosis of CVS to minimize its impact on working performance. Accordingly, it is recommended to organize university-based awareness programs regarding CVS for working personnel. [ABSTRACT FROM AUTHOR]

Abstract Background Sonographers have reported a high occurrence of musculoskeletal pain for more than 25 years. Assessments of occupational risk factors have previously been based on cross-sectional surveys. The aim of this longitudinal study was to determine which factors at baseline that were associated with neck/shoulder and elbow/hand pain at follow-up. Methods A questionnaire was answered by 248 female sonographers at baseline and follow-up (85% of the original cohort). 208 were included in the analyses. Physical, visual, and psychosocial work-related conditions were assessed at baseline. Pain in two body regions (neck/shoulders and elbows/hands) was assessed at both baseline and follow up. Results Pain at baseline showed the strongest association with pain at follow-up in both body regions [prevalence ratio (PR) 2.04; 95% confidence interval (CI) 1.50–2.76], for neck/shoulders and (PR 3.45; CI 2.29–5.22) for elbows/hands. Neck/shoulder pain at follow-up was associated with inability of ergonomic adjustments at the ultrasound device (PR 1.25; CI 1.05–1.49), a high mechanical exposure index (PR 1.66; CI 1.09–2.52), and adverse visual conditions (PR 1.24; CI 1.00–1.54) at baseline. Moreover, among participants with no neck/shoulder pain at baseline, high job demands (PR 1.78; CI 1.01–3.12), and a high mechanical exposure index (PR 2.0; CI 0.98–4.14) predicted pain at follow-up. Pain in the elbows/hands at follow-up was associated with high sensory demands at baseline (PR 1.63; CI 1.08–2.45), and among participants without pain at baseline high sensory demands predicted elbow/hand pain at follow-up (PR 3.34; CI 1.53–7.31). Conclusion Pain at baseline was the strongest predictor for pain at follow-up in both body regions. We also found several occupational factors at baseline that were associated with pain at follow-up: inability to adjust equipment, adverse visual conditions, a high MEI, high job demands and high sensory demands. These results point at a possibility to influence pain with better ergonomics.

New type desktop head-up display (HUD) can reduce visual fatigue and protect vision through long viewing distance. In this study, participants evaluated visual performance, fatigue, and discomfort of desktop HUD under two contrast polarity (N = 36) and five display luminance levels (N = 21). A positive polarity advantage was found over negative in visual fatigue and discomfort ( p  < .05). Statistically significant effect of luminance was found on visual performance, fatigue, and discomfort ( p  < .05). The calculated optimum display luminance by the proposed inverted-U fitted model was 153 cd/m 2 under 300 lx, higher than that of traditional desktop displays. It is speculated that higher luminance is required to offset the reduction in contrast sensitivity due to smaller target angular size, which caused by longer viewing distance. These findings suggest that positive polarity and 153 cd/m 2 can be used to improve performance and avoid fatigue and discomfort when utilising desktop HUD under 300 lx.

As visual displays for computers, televisions, tablets and mobile phones grow brighter (and larger), concerns about their emissions of short‐wavelength ("blue") light have emerged. This paper reviews the evidence underling these concerns, including the potential for blue‐light hazard, visual discomfort, and circadian disruption. [ABSTRACT FROM AUTHOR]

Background: Sonographers have reported a high occurrence of musculoskeletal pain for more than 25 years. Assessments of occupational risk factors have previously been based on cross-sectional surveys. The aim of this longitudinal study was to determine which factors at baseline that were associated with neck/shoulder and elbow/hand pain at follow-up.Methods: A questionnaire was answered by 248 female sonographers at baseline and follow-up (85% of the original cohort). 208 were included in the analyses. Physical, visual, and psychosocial work-related conditions were assessed at baseline. Pain in two body regions (neck/shoulders and elbows/hands) was assessed at both baseline and follow up.Results: Pain at baseline showed the strongest association with pain at follow-up in both body regions [prevalence ratio (PR) 2.04; 95% confidence interval (CI) 1.50-2.76], for neck/shoulders and (PR 3.45; CI 2.29-5.22) for elbows/hands. Neck/shoulder pain at follow-up was associated with inability of ergonomic adjustments at the ultrasound device (PR 1.25; CI 1.05-1.49), a high mechanical exposure index (PR 1.66; CI 1.09-2.52), and adverse visual conditions (PR 1.24; CI 1.00-1.54) at baseline. Moreover, among participants with no neck/shoulder pain at baseline, high job demands (PR 1.78; CI 1.01-3.12), and a high mechanical exposure index (PR 2.0; CI 0.98-4.14) predicted pain at follow-up. Pain in the elbows/hands at follow-up was associated with high sensory demands at baseline (PR 1.63; CI 1.08-2.45), and among participants without pain at baseline high sensory demands predicted elbow/hand pain at follow-up (PR 3.34; CI 1.53-7.31).Conclusion: Pain at baseline was the strongest predictor for pain at follow-up in both body regions. We also found several occupational factors at baseline that were associated with pain at follow-up: inability to adjust equipment, adverse visual conditions, a high MEI, high job demands and high sensory demands. These results point at a possibility to influence pain with better ergonomics. [ABSTRACT FROM AUTHOR]

The present study aimed to identify whether or not an increase in ciliary-muscle contraction force, when the eye-lens is adjusted for viewing at a near distance, results in an increase in trapezius muscle activity, while performing a natural work task. Twelve participants, ranging in age from 21 to 32 years, performed a computer-mouse work task during free gaze conditions. A moving visual target was tracked with a computer mouse on a screen placed at two different distances from the eyes, 25 cm and 50 cm. Tracking performance, eye accommodation, and bilateral trapezius muscle activity were measured continuously. Ciliary-muscle contraction force was computed according to a formula which takes into account the age-dependent, non-linear relationship between the contraction force of the ciliary muscle and the produced level of eye accommodation. Generalized estimating equations analyses were performed. On the dominant hand side and for the nearest screen distance, there was a significant effect of ciliary-muscle contraction force on the trapezius muscle activity (p < 0.001). No other effects were significant (p > 0.05). The results support the hypothesis that high visual demands, during computer mouse work, increase ciliary muscle contraction force and contribute to a raise of the sustained level of trapezius muscle activity. The current study specifically clarifies the validity of the relationship between ciliary-muscle contraction force and trapezius muscle activity and demonstrates that this relationship is not due to a general personality trait. We conclude that a high level of ciliary muscle contraction force can contribute to a development of musculoskeletal complaints in the neck-shoulder area. [ABSTRACT FROM AUTHOR]

Purpose: To extend our knowledge of the functional linkages between visual fatigue and regional cerebral prefrontal cortex (PFC) oxygenation, we measured time related hemodynamic changes over the right dorsolateral prefrontal cortex (dlPFC) during convergence load under conflicting stimulus-to-accommodation and stimulus-to-vergence eye movements with and without concurrent mental load. Methods: Twenty healthy participants with a median age of 28 years (range: 18–44 years) fixated upon a vertical bar presented separately to the left and right eyes, using polarized filters, during four counterbalanced 10-min periods: (i) no accommodation/vergence conflict (Control, Ctrl); (ii) added convergence load and accommodation/vergence conflict (Conv); (iii) added cognitive load only (Cog) and; (iv) a combination of added cognitive and convergence load and accommodation/vergence conflict (Cc). Viewing distance was 65 cm. Non-invasive measurements of hemodynamic activity over the dlPFC were quantified by functional near-infrared spectroscopy (fNIRS). During the two-convergence load conditions, the horizontal disparity of the two bars varied dynamically from no disparity to a disparity set 20% below the individual threshold for diplopia. Cognitive load was induced by the n -back-2 test which required the subject to memorize and recall the changing colors of the horizontal bars and decide when a given color was the same as that occurring two colors previously. fNIRS data were averaged over 10-s windows centered at 0, 2, 4, 6, 8, and 10 min of each task, subtracted from a 20-s baseline window immediately preceding the visual task, and then represented as changes in oxygenated hemoglobin (ΔHbO2), deoxygenated hemoglobin (ΔHHb) and total hemoglobin (ΔtHb). Results: Linear mixed model analyses showed that hemodynamic activity was systematically influenced by time (p < 0.001). The group-averaged time-related level of change across the viewing conditions did not differ when compared with one another (p > 0.05). Larger convergence eye-movement responses under conflicting stimulus-to-accommodation, and stimulus-to-vergence over time, increased ΔHbO2 and ΔtHb only in condition Cc and after 8 min of task time (p < 0.10 for min-6 and min-8: p < 0.05 for min-10). Discussion: Collectively, our data suggest that HbO2, HHb, and tHb, recorded over the dlPFC with fNIRS, can be used to assay the degree to which supervisory oculomotor control processes are activated during visually deficient near work. [ABSTRACT FROM AUTHOR]

In laparoscopy, novel three-dimensional laparoscopic vision systems (3D LVS) without glasses (3D−) have been invented. While standard 3D LVS with glasses (3D+) have shown advantages over original two-dimensional systems, quantitative comparisons of surgical performance between 3D− and 3D+ systems are still lacking. The aim is to compare the systems in simulated robotic surgery tasks. In a crossover study, 18 medical students performed four basic laparoscopic tasks in the validated Simball Box simulator with authentic surgical instruments by using the 3D+ and 3D− systems. Performance was measured by the number of errors and the task’s duration. Subjective ratings of perceptions and preference were assessed after each test. There were significant, but still minor, advantages for the conventional 3D+ system regarding spatial orientation and sense of depth. Overall, ten and eight subjects preferred 3D+ and 3D− systems, respectively. No significant differences were found in performance, post-operative physicals or eye symptoms. The novel 3D− system was similar to the conventional 3D+ system regarding performance and overall preference, while there were minor advantages for the 3D+ system in the subjective ratings. Since the 3D− system is a new invention, it should have a higher potential of usability improvements.

The efficiency of lighting installations is a major challenge concerning Governments, productive sectors and individuals. However, the importance of accurate lighting in some areas, especially those related to Health and Wellbeing is so critical that the constraints of energy efficiency and sustainability are not always a priority. This situation has become more critical with the current boom in the application of non-visual effects of light to these areas. In this study, the effects oftwo different kinds of lighting on femalevictims of gender violence are compared and analyzed in terms of positive results and impact on energy consumption and sustainability. The lighting technologies used are integrated in facilities where these women carry out different activities aimed at their integration into daily life after their traumatic experiences. The results are expected to become a tool for professionals working with these collectives and for installation designers. In spite of the well-known effects of cold light, especially for tasks involving arousal, sleepiness and other critical variables, it is demonstrated that daylight, which is obviously cheaper from productive and environmental perspectives, is better for this application. [ABSTRACT FROM AUTHOR]

Aim: To investigate if trapezius muscle activity increases over time during visually demanding near work. Methods: The vision task consisted of sustained focusing on a contrast-varying black and white Gabor grating. Sixty-six participants with a median age of 38 (range 19-47) fixated the grating from a distance of 65 cm (1.5 D) during four counterbalanced 7-min periods: binocularly through −3.5 D lenses, and monocularly through −3.5 D, 0 D and +3.5 D. Accommodation, heart rate variability and trapezius muscle activity were recorded in parallel. Results: General estimating equation analyses showed that trapezius muscle activity increased significantly over time in all four lens conditions. A concurrent effect of accommodation response on trapezius muscle activity was observed with the minus lenses irrespective of whether incongruence between accommodation and convergence was present or not. Conclusions: Trapezius muscle activity increased significantly over time during the near work task. The increase in muscle activity over time may be caused by an increased need of mental effort and visual attention to maintain performance during the visual tasks to counteract mental fatigue. [ABSTRACT FROM AUTHOR]

To solve the problem of artificial calculation and mapping error in traditional visual ergonomics evaluation, based on the analysis of the human vision characteristics, the eyellipse and H point used in the car vision design principle are introduced, and the visual ergonomics evaluation model of the oil rig driller control room is established by combining the computer aided ergonomics design technology. Taking CATIA as the secondary development platform, the visual ergonomics evaluation system of the driller control room is programmed by VB, which realizes the accurate and rapid positioning of eyes with different percentile human body model. Finally, a case illustrates that the system is practical and able to satisfy the visual assessment requirements of the human-machine interface layout of the driller control room. [ABSTRACT FROM AUTHOR]

BACKGROUND: The static posture of postal workers when sorting mail can lead to musculoskeletal discomfort. Research has shown a connection between eyestrain and upper-body musculoskeletal discomfort in general, including postal workers. A previous study of postal workers found that most of those with eye strain were in need of a new correction in their existing spectacles. OBJECTIVE: Evaluate intervention effects on eyestrain and musculoskeletal discomfort with new spectacles for postal workers. METHODS: Postal workers subjectively reported eyestrain, musculoskeletal discomfort and their opinions of the visual environment via questionnaires pre- and post-intervention. After an eye examination the postal workers were divided into two groups: those who needed new spectacles and those who did not. RESULTS: Those who needed new spectacles showed a higher prevalence of eyestrain and musculoskeletal discomfort pre-intervention. Post-intervention, the postal workers rated their vision better and the average eyestrain and musculoskeletal discomfort decreased for both groups. These workers also experienced a decrease in discomfort on the left (static) side of the neck while sorting mail. CONCLUSION: An intervention providing the optimal correction reduces eyestrain and decreases musculoskeletal discomfort, especially from the neck. [ABSTRACT FROM AUTHOR]

Ergonomists and optometrists often have mutual clients/patients with complex visual needs in the workplace but communication between the professionals is usually indirect through the client/patient. This paper describes a joint professional development meeting between optometrists and ergonomists in Canberra, Australia, which included a discussion to explore how to improve communication between the two professions. Optometrists and ergonomists reported they would prefer more information before conducting assessments and providing advice. Vision screening forms commonly in use for computer workers were viewed as inadequate to meet these needs. Communication between the two professions was hampered by absence of contact details of the optometrist/ergonomist, perceptions that the other profession is too busy to talk, privacy considerations in sharing information and funding issues for shared care arrangements. There are opportunities for increasing awareness of good vision in workplaces. Communication between optometrists and ergonomists can be improved by developing information-sharing documents relevant to modern workplaces. [ABSTRACT FROM AUTHOR]

BACKGROUND: During many years of occupational stress research, mostly within the German governmental program for "Humanization of Work Life'', remarkable deficits concerning visual work were seen, the most striking being the lack of cooperation between the different experts. OBJECTIVE: With regard to this article hard arguments and ideas for solutions had to be found. METHODS/PARTICIPANTS: A pilot study in 21 enterprises was realized (1602 employees with different visual work tasks). A test set of screening parameters (visual acuity, refraction, phoria, binocular cooperation and efficiency, accommodation range and color vision) were measured. The glasses and/or contact lenses worn were registered and the visual tasks analyzed. In work at visual display units (VDU) the eye movements were recorded and standardized questionnaires were given (health, stress, visual work situation). Because of the heterogeneity of the sample only simple statistics were applied: in groups of different visual work the complaints, symptoms, hassles and uplifts were clustered (SAS software) and correlated with the results of the visual tests. Later a special project in 8 companies (676 employees) was carried out. The results were published in [14].RESULTS: Discomfort and asthenopic symptoms could be seen as an interaction of the combination of tasks and working conditions with the clusters of individual functionalisms, frequently originating in postural compromises. Mainly three causes for stress could be identified: 1. demands inadequate with regard to intensity, resolution, amount and/or time structure; 2. prevention of elementary perceptive needs; 3. entire use of partial capacities of the visual organ. Symptoms also were correlated with heteronomy. Other findings: influence of adaptation/accommodation ratio, the distracting role of attractors, especially in multitasking jobs; influence of high luminance differences. Dry eyes were very common, they could be attributed to a high screen position, low light, monotonous tasks and office climate. For some parameters a diurnal rhythm could be identified. Nowhere special programs for ageing employees were found: the right glasses; retinal problems and signs of destabilization of vision. CONCLUSIONS: In all enterprises, the ergophthalmological and visual ergonomic knowledge of the occupational physicians was poor, visual ergonomists were not available and there was only very poor cooperation with ophthalmologists and optometrists, the first of whom additionally had not much knowledge of modern work. [ABSTRACT FROM AUTHOR]