Background: Digital Eye Strain (DES) is one of the health effects from overuse of digital devices. Although the use of digital devices and the visual problems have been reported among adults in many studies, DES is rarely investigated in children.

Objective: To determine the prevalence and associated risk factors of digital eye strain (DES) among the lower secondary school students.

Materials and Methods: The present report was an analytical cross-sectional study, employed self-administered questionnaires to determine the prevalence and associated factors of digital eye strain among students in lower secondary schools. Data were collected from 15 June to 30 August 2016 in 3 schools in Pathumthani province, Thailand. Data were analyzed by Chi-square test and multivariate regression to show the relationship between studied variables and digital eye strain.

Results: There were total of 550 questionnaires collected (94.01% responsed rate). The symptoms of DES were reported among 460 students (94.84%). The associated risk factors of DES when analyzing with multivariate logistic regression were gender (adjusted OR 3.88, 95% CI 1.38, 10.92), viewing distance (adjusted OR 3.57, 95% CI 1.28, 9.93) and duration of use on weekend over 2 hr per day (adjusted OR 7.62, 95% CI 3.25, 17.82).

Conclusion: The prevalence of DES in the lower secondary school students was as high as in adults. In Thailand, there are no guidelines on the use of digital devices especially smartphones. Therefore, the present study recommends that smartphone use should be less than 2 hours/day and viewing distance more than 34 mm in order to protect health hazards from smartphone.

Keywords: Digital eye strain, Viewing distance, Children, Smartphone