Objective Assessment of Active Display Screen Fixation Among Office Workers Using an Innovative Nonwearable Acquisition System: A Pilot Study

Background: Occupational risk assessments of VDT users are usually hindered by the variability of tasks that office workers perform. Digital eye strain is related to the amount of work time dedicated to screen fixation. Purpose: This study aimed to improve the risk assessment of VDT workers by introducing an advanced version of software developed at the University of Brescia. Methods: The prototype enables the recording of the times in front of the screen and those in which the operator actively fixes. It was tested on 30 employees from different offices. The system includes a webcam placed over the workers’ screens and connected with a laptop running specifically developed monitoring software. This experiment required worker-to-worker calibration of the system by the investigators. Results: The obtained data allowed us to distinguish between the period of screen fixation and the presence in front of the monitor. The visual activity varied greatly on a daily basis because of the differences between tasks. The mean facial detection time was approximately 48%, whereas the mean eye fixation time was 29%. Conclusions: The results suggest that our prototype is a promising tool for investigating the relative contributions of screen fixation to the development of digital occupational eye strain.