Analysis of Work-Related Factors Influencing the Health of Visual Display Terminal Workers

Various studies of visual display terminal (VDT) work have shown the need of investigating causal relationshipsb etween characteristicosf VDT work and health effects. in this study, the possible causal factors for modeling the above relationships were examined based on the data from a questionnaire survey at a travel agency. The questionnaire included various items related to VDT job type (e.g., travel reservation, data entry, word processing), VDT work time, display legibility, workstation dimensions, work environment, usability of VDT, job characteristics (e.g., monotony, cooperation, autonomy), eye fatigue and musculoskeletal symptoms. Principal component factor analysis was performed to construct indices of eye fatigue and musculoskeletal symptoms as health effects and other indicesf or VDT work conditions. Two distinct factors recognized for eye fatigue symptoms were “impaired accommodaion” and “eye pain” and two factors for musculoskeletal symptoms were “neckshoulder areas” and “finger-arm areas”. Data analysis for 656 VDT workers showed that the VDT work time of travel reservation and professional (computer programming) workers was longer than that of data entry and word processing workers. Professional workers reported intensively the impaired accommodation symptoms, and data entry workers frequently reported the finger-arm symptoms. Multiple regression analysis based on the four different indices of health effects as dependent variables was performed for male workers of two VDT job types. This analysis gave a better picture of the relationships between various conditions of VDT work and the health effects. It was shown that the different VDT job types had different significant contributors to each indicator of health effects. For example, the limitation of computer hardware such as response delay was one of the significantc ontributors to the impaired accommodation, and the eye pain and the neck-shoulder symptoms for travel reservation workers. These findings suggested that it was important to separate VDT job types in identifying a causal structure modeling of health effects by VDT work