Field observations of display placement requirements and character size for presbyopic and prepresbyopic computer users

User experience with ultrawide curved displays: A mixed methods analysis

Due to the trend of replacing dual displays with ultrawide (UW) curved displays, we used a mixed methods analysis to investigate the user experience with UW curved displays. We conducted an experimental laboratory study that quantified user self-selected positions for three displays - 24 in. flat panel, and 34 in. and 40 in. UW curved displays. Participants were first provided with a familiarization protocol, and they then positioned the display. The self-selected UW display viewing distances were within current recommendations; however, viewing distance increased with display size, potentially challenging small work surface depths and may have been in response to feeling "overwhelmed" by larger displays. Head twist range of motion increased with display width. While all displays were within recommendations, participants commented that less head twisting was a factor in choosing the 34 in. over the 40 in. display. Practitioners should assess potential workstation limitations and the potential impact on neck twist angles when installing ultrawide displays.

Analysis of real-world visual ergonomics at the visual display unit

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.

Association Between Types of Chronic Disease and Receiving Workplace Accommodations: A Cross-Sectional Study of Japanese Workers

OBJECTIVE

This study aimed to evaluate the association between the type of chronic disease and receiving workplace accommodations.

METHODS

This online cross-sectional study analyzed a self-reported questionnaire administered in Japan. A total of 6775 full-time workers who reported needing work accommodations were included.

RESULTS

Workplace accommodations were more likely to be provided for workers with cancer, mental illness, and benign gynecological disorders than for workers with no disease under treatment. In contrast, workplace accommodations were less likely for workers with low back pain and skin diseases.

CONCLUSIONS

Receiving workplace accommodations depends on the type of chronic disease. Chronic diseases for which workers frequently receive workplace accommodations may be those for which support is encouraged by law. It is necessary to support workers with chronic diseases that do not receive adequate workplace accommodations.

Analysis of Daily Visual Habits in a Presbyopic Population

Purpose

To evaluate and report the visual habits and requirements of a sample of presbyopic patients using an advanced sensor.

Methods

Transversal study collecting clinical data from 40 presbyopes candidates for presbyopia-correction intraocular lens (IOL) implantation with mean age of 61.0 years (43-80 years). A complete ophthalmological examination was performed in all patients including visual, refractive, an ocular biometric analysis. Furthermore, patients were instructed about the use of the Vivior Monitor system (Vivior AG, Zürich, Switzerland), which consists of a series of sensors attached to the rim of the patient's glasses that capture information about the visual behavior of the patient. This device was worn for a period of 36 hours or more. The data collected were transferred to a database and analyzed.

Results

Mean percentages of time dedicated to distance, intermediate, and near vision were 27.25 ± 11.93% (5-65%), 30.23 ± 9.36% (12-50%), and 42.53 ± 14.96% (13-78%), respectively. Mean percentages of time performing activities under photopic, mesopic, and scotopic conditions were 37.08 ± 23.20% (5-87%), 33.65 ± 13.84% (6-67%), and 29.28 ± 17.03% (4-65%). The percentage of time with digital screens ranged from 2% to 48%. Age was significantly correlated with the percentage of time dedicated to distance vision (r = 0.317, p=0.047) and to activities performed under photopic conditions (r = -0.344, p=0.030).

Conclusions

Distance and illumination conditions used to perform different daily life visual activities vary significantly among presbyopes, with a trend to the dedication of more time to intermediate and near visual activities performed under photopic and mesopic conditions. Data interpretation should be done with care until a proper validation of the device used.

Prevalence of Computer Vision Syndrome and Its Relationship with Ergonomic and Individual Factors in Presbyopic VDT Workers Using Progressive Addition Lenses

This cross-sectional study estimated computer vision syndrome (CVS) prevalence and analysed its relationship with video display terminal (VDT) exposure, as well as sociodemographic, refractive, environmental, and ergonomic characteristics in 109 presbyopic VDT workers wearing progressive addition lenses (PALs). Usual spectacles were measured with a lens analyser, and subjective refraction was performed by an optometrist. CVS was measured with the CVS-Q©. VDT exposure was collected. Ergonomic evaluations were conducted in a normal working posture looking at the screen. Air temperature and relative humidity were measured (thermohygrometer), and illumination was measured (luxmeter). Descriptive analysis and differences in CVS prevalence, as a function of the explanatory variables, were performed (chi-square test). Multivariate logistic regression was used to identify factors associated with CVS (OR and 95% CI). The mean age was 54.0 ± 4.8 years, and 43.1% were women. The mean hours of VDT use at work was 6.5 ± 1.3 hours/day. The prevalence of CVS was 74.3%. CVS was significantly associated with women (OR 3.40; 95% CI, 1.12–10.33), non-neutral neck posture (OR 3.27; 95% CI, 1.03–10.41) and altered workplace lighting (OR 3.64; 95% CI, 1.22–10.81). Providing training and information to workers regarding the importance of adequate lighting and ergonomic postures during VDT use is advised to decrease CVS and increase workplace quality of life.

Effect of unifocal versus multifocal lenses on cervical spine posture in patients with presbyopia

Significance. There are many environmental considerations which may or may not lead to the development of faulty cervical mechanics. The design of near-vision lenses could contribute to the development of such cervical dysfunction and consequently neck pain. Decision-making regarding the proper type of lens prescription seems important for presbyopic individuals. Purpose. To investigate the effect of unifocal and multifocal lenses on cervical posture. Methods. Thirty subjects (18 females and 12 males) participated in the study with an age range from 40 to 64 years. Each subject wore consequently both unifocal and multifocal lenses randomly while reading. Lateral cervical spine X-ray films were taken for each subject during each lens wearing. X-ray films were analyzed with digital software (AutoCAD 2D version 22) to measure segmental angles of the cervical vertebrae (occiput/C1, C1/C2, C2/C3, C3/C4, C4/C5, C5/C6, C6/C7, C3/C7, C0/C3, and occiput/C7). Results. Higher significant extension angles were observed in the segments C0/C7, C1/C2, C5/C6, C6/C7 and C3/C7 (p < 0.05) during multifocal lens wearing, in contrast to higher flexion angles between C3/C4 and C4/C5 (p < 0.05) when wearing unifocal lenses. Conclusion. Multifocal lens spectacles produce increased extension in the cervical vertebrae angles when compared with the use of unifocal lenses.