Smartphone Use Associated with Refractive Error in Teenagers: The Myopia App Study
The purpose of this study is to investigate the association between smartphone use and refractive error in teenagers using the Myopia app.
A cross-sectional population-based study was conducted with a total of 525 teenagers 12 to 16 years of age from 6 secondary schools and from the birth cohort study Generation R participated.
A smartphone application (Myopia app; Innovattic) was designed to measure smartphone use and face-to-screen distance objectively and to pose questions about outdoor exposure.
Participants underwent cycloplegic refractive error and ocular biometry measurements.
Mean daily smartphone use was calculated in hours per day and continuous use as the number of episodes of 20 minutes on screen without breaks.
Linear mixed models were conducted with smartphone use, continuous use, and face-to-screen distance as determinants and spherical equivalent of refraction (SER) and axial length-to-corneal radius (AL:CR) ratio as outcome measures stratified by median outdoor exposure.
Dutch teenagers spent almost 4 hours per day on their smartphones.
Episodes of 20 minutes of continuous use were associated with more myopic refractive errors, particularly in those with low outdoor exposure.
This study suggested that frequent breaks should become a recommendation for smartphone use in teenagers.
Future large longitudinal studies will allow more detailed information on safe screen use in youth.