Prevalence and risk factors of visual fatigue in computer users

Working with Visual Display Terminals (VDTs) can be associated with visual complaints particularly visual fatigue and symptoms including headache, disruption in continuing the work and ocular disorders. The objective of the present study was to determine the prevalence of visual fatigue and its related risk factors in computer users of Kermanshah University of Medical Sciences in 2013. This descriptive-analytical study was achieved on 260 computer users. The data were collected by Visual Fatigue, demographic and job questionnaires. For data analysis, Spearman, Mann-Whitney and Kruskal-Wallis tests were used. The mean (SD) age of the users was 36.74 (7.74) and daily working time with VDTs was 5.85 (2.28) hours. Visual fatigue score was 2.99 (1.97), so that 32.3% of computer users had severe eye fatigue. Meanwhile, 45.4, 21.9, 32.7 and 46.2 percentage of users suffered severely from eye strain, visual impairment, eye-surface disorder and extra-ocular problems. Visual fatigue incidence and its compliments were significantly increased with increasing of age, work experience and daily working hours with computer (p<0.05). Visual fatigue was higher in users wearing glasses than those not wearing glasses (p<0.001) and was lower in monitor to window angle of 90º than two other monitor to window positions of 0º (p=0.041) and 180º (p=0.036). The prevalence of visual fatigue among computer users was very high. Visual fatigue and its serious consequences can be prevented by applying the principles of ergonomics such as regular and short breaks, looking at distant objects, blinking regularly and reducing the direct and indirect glares.