隨著視覺顯示器（Visual Display Terminals, VDTs）快速大量運用在人們之日常工作中，因其而引發之相關健康問題，尤其是視覺及肌肉骨骼不適問題，已經引起廣泛的注意。而在這些會引起上述問題之因素中，VDT工作站偏好設定（preferred settings）及與工作相關之心理社會因素（psychosocial factors）是相當受到關注的。許多研究指出，若VDT工作站能依使用者個人偏好來設定，視覺及肌肉骨骼不適問題將可獲得改善。因此能符合人體計測數值及個人偏好設定之工作站設計已經被廣泛認同。然而國內並無相關VDT工作站偏好之測定數據。此外，對於與工作相關之心理社會因素為何會造成視覺及肌肉骨骼不適問題之原因及機制目前仍然不清楚，但是有許多研究顯示，心理社會因素對造成視覺及肌肉骨骼不適之影響遠大於原先大家所預期的。
因此本研究以台灣新竹某半導體製造廠之VDT使用者為研究對象，調查本土VDT使用人員之工作站偏好設定數據及人因訓練課程對其偏好設定之影響，並對於VDT使用者在一般不完全可調VDT工作站工作時之偏離（deviate）個人偏好設定對身體不適影響之關聯性加以探討。此外，一些心理社會因素及其與一般生理及人因因素（physical/ergonomics factors）對視覺及肌肉骨骼不適狀況之影響也將加以評估。一些評估後改善建議已被該公司採用並即將進行實際改善與評估。

在VDT工作站偏好設定數據方面，研究結果顯示，兩種常見VDT電腦工作站：PC及CAD工作站，其在桌高及椅高等偏好設定上，並無顯著差異，主要差異在於CAD工作站需要較充裕之螢幕與桌緣距離以提供舒適之眼睛與螢幕距離設定，實驗結果也顯示，國人偏好之桌高與椅高也明顯低於西方人之相關偏好數據。而針對人因訓練課程對個人偏好設定影響方面，實驗結果顯示，絕大多數VDT使用者採用相同之調整策略，先調整椅高與桌高，其次才是螢幕高度，研究結果亦發現並不是所有VDT使用者一開始均能適當調整工作站設定，即使在於一完全可調之工作站上，因此相關之人因訓練課程仍是必須的。

而對在一般不完全可調VDT工作站工作時，偏離個人偏好設定對身體不適影響，回歸模型之研究結果顯示，在眼睛與螢幕距離、肘高與鍵盤高度差異及身體傾斜角度上之偏離是造成眼睛及肌肉骨骼不適最顯著之因素。最後，針對心裡社會因素對視覺及肌肉骨骼不適之影響之評估方面，研究結果顯示，在生理及人因方面之變數對於視覺與上肢之不適影響較為顯著，但是對於背部與下肢之不舒適問題上，心理社會因素則是較主要之因素。

此研究完整及系統化評估會造成VDT工作站使用人員身體不適之相關風險因素。其研究結果應能作為電腦工作站設計人員之參考並會對台灣VDT工作站使用人員有所助益。

Along with the dramatically expanding use of visual display terminals (VDTs), associated health problems, predominately visual and musculoskeletal discomforts, have become subjects of growing concerns. Among those attributed risk factors, VDT workstation preferred settings and work-related psychosocial factors are two of the most concerned ones.
Many studies have shown that the physical discomforts were reduced with preferred settings. Therefore, incorporating the considerations of anthropometrics and individual preferred settings while designing VDT workstation has been embraced as a primary measure for preventing the above problems. However, almost no VDT workstation preferred settings data for Taiwanese works has been ever reported. As for the work-related psychological factors, the etiologic mechanisms of their effects on health problem are still poorly understood. However, much evidence has suggested a larger role for workplace psychosocial factors in producing adverse health effects than was previously though to be the case.

This study was conducted in a semiconductor manufacturing company in Hsinchu, Taiwan. The purpose of this study was to investigate the preferred settings of VDT works. The effects of ergonomics training on preferred settings and the deviations of field workstation from preferred settings would also be assessed. Besides, the contribution of several alleged psychosocial risk factors (e.g., lack of social support, monotonous work, lack of job control, and intensified workload) on physical discomforts and their interactions with physical/ergonomic variables would be evaluated. After assessment, countermeasures to reduce VDT physical discomforts were proposed. Some of these are going to be employed and evaluated in the company.

Regarding the preferred settings of VDT workstation, results showed that the main differences on preferred settings between PC and CAD workstation were head-neck posture and gaze angle that were mainly caused by the difference in monitor size. Since neither the desk height and the monitor stand height, nor the seat height showed significant difference between the two types of workstations, similar adjustable dimensions may be specified for the design of both workstations. Except that the CAD workstation should allow for greater monitor screen to desk edge distance. In addition, comparing the preferred settings with previous reports based on western data, a consistently and significantly lower preferred monitor height, keyboard height and seat height were observed for the Taiwanese VDT users. As for the effects of ergonomics trainings on preferred settings, results showed that all subjects took a same adjustment strategy on the fully adjustable VDT workstation. They set the monitor height right after the setting of seat height and desk height. Besides, the lecture-based ergonomics training was found helpful because not all of the subjects were aware of the advantages of using posture supports and document holder before the training.

As for the effects of deviation from preferred settings on physical discomforts, results showed that deviations in eye to monitor distance, in elbow height-keyboard height difference and in trunk inclination angle were the most predictive variables on physical discomforts. Finally, regarding the relationships between psychosocial factors and physical discomforts, results showed that physical/ergonomics variables were found more dominant than psychosocial factors for the visual and upper extremity discomforts; but for the back and lower extremity discomforts, psychosocial variables were the leading factors.

This research is a comprehensive and systematic investigation of the associated factors in the physical discomforts problems of the VDT users. The result can serve as reference for VDT workstation designer and so be beneficial to Taiwanese VDT users.

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