Ergonomic predictors of visual system complaints in VDT data entry work.
Schleifer-LM; Sauter-SL; Smith-RJ; Knutson-S
Behav Inf Technol 1990 Aug; 9(4):273-282
A study of the relationship between ergonomic factors and visual complaints in video display terminal (VDT) operators was conducted. The study group consisted of 905 VDT operators, 87% of whom were female, at two state government agencies. Approximately 68% were data entry machine operators. The subjects completed a questionnaire to obtain information on demographic and personal characteristics, hours of VDT use, and visual complaints. Detailed ergonomic evaluations of the workstations of 40 randomly selected data entry machine operators were performed. The data were analyzed by stepwise regression techniques using the questionnaire data and ergonomic factors as independent variables and ocular and perceptual discomfort as dependent variables. Ocular and perceptual discomfort decreased with age and use of corrective eyewear; however, age and eyewear explained only 5% of the variance in ocular and perceptual discomfort associated with VDT use. Variables related to reading distance and gaze angle explained 49 and 38% of the variance in ocular and perceptual discomfort, respectively. Screen reflection and worksite illumination were not predictive of ocular and perceived discomfort in the ergonomic analysis. Glare explained 14% of the variance in ocular discomfort and 10% of the variance in perceptual discomfort in the questionnaire survey. Workstations with high levels of keyboard illumination were associated with increased visual discomfort. The authors suggest that ergonomic factors because of their effect on visual accomodation play a significant role in the visual strain experienced by VDT operators.
Video-display-terminals; Keyboard-operators; Ergonomics; Occupational-health; Statistical-analysis; Eye-strain; Questionnaires; Lighting; Work-environment
Behaviour and Information Technology