Kids spend more time now than ever doing near tasks on their smartphones, and it may be affecting their eyes. A recent study reports that school-aged children with myopia appear to use about twice as much data as their normal vision counterparts, which may indicate a link between myopia and smartphone data usage.

The investigation, published online in Clinical and Experimental Optometry, examined the results of questionnaires filled out by secondary and tertiary level students (n=418) about their patterns of smartphone usage and their attitudes about potential myopia risk.

The research team from Ireland considered data usage over an extended period as the primary and objective indicator of phone use, and average daily time spent using a smartphone was quantified by self-reported estimates. An optometrist verified each participant’s refractive status.

Among the 418 students in the study, 99% owned smartphones. Average daily smartphone data and time usage was 800.37±1,299.88MB and 265.16±168.02 minutes, respectively.

Myopic students used almost double the amount of smartphone data, at 1,130.71±1,748.14MB per day compared with non-myopes, who used an average of 613.63±902.15MB daily, although smartphone time usage was not significantly different (12% higher in the myopes). The study also found myopic refractive error was significantly associated with increasing daily smartphone data usage, as well as increasing age and number of myopic parents.

Also of note: 73% of students believed that digital technology could hurt their eyes.

“Given the serious nature of the ocular health risks associated with myopia, our findings indicate that this relationship merits more detailed investigation,” the researchers wrote in their paper.