Correlation between handheld digital device use and asthenopia in Chinese college students: a Shanghai study.

Asthenopia appears to be common among college students in China. Preventative measures against asthenopia include limiting the amount of time spent using digital devices in bed (<0.5 h), adopting a posture of lying on one's back while doing so and engaging in aerobic exercise for more than one hour per day. Furthermore, studies on this topic are needed.