Evaluation of Stereo Acuity and Depth Perception in Adolescents and Young Adults: Insights from a Cross-Sectional Study

Objectives: This study aimed to evaluate stereoacuity and depth perception in adolescents and young adults (12–26 years) and to determine their association with refractive errors, digital device use, age, and socioeconomic status. It further assessed the diagnostic utility of the Titmus Fly Test and Random Dot Stereo Test in identifying binocular vision dysfunction. Methods: A cross-sectional study was conducted among 784 participants recruited from schools and clinics. Visual acuity, stereoacuity, accommodation, and near point of convergence were measured under standardized conditions. Participants were grouped by refractive error, screen time exposure (≤6 h vs. >6 h/day), and socioeconomic status. Stereoacuity was categorized as normal, mild, or moderate-to-severe. Statistical analyses included descriptive statistics, Pearson’s correlation, multiple regression, odds ratios, and subgroup comparisons, with significance set at p < 0.05. Findings: Overall, 35% of participants demonstrated stereoacuity deficits. Myopia was strongly associated with impairment; each 1-diopter increase in myopia corresponded to a 12% reduction in stereoacuity, and high myopes had a 42% failure rate in achieving normal levels. Prolonged digital device use (>6 h/day) nearly doubled the risk of deficits (OR=1.80, 95% CI: 1.42–2.25). Age-related decline was observed beyond 22 years, while hyperopia and socioeconomic status were weaker predictors. Subgroup analysis showed progressively higher impairment with age and screen time. Corrective lenses significantly improved stereoacuity. Novelty: This is the first large-scale Indian study to report stereoacuity and depth perception patterns in adolescents and young adults, a group often overlooked in vision research. The findings highlight myopia progression and digital overuse as dominant risk factors, justifying the inclusion of stereoacuity screening in school and university health programs. They also provide a basis for innovative interventions such as virtual reality-based binocular therapy and inform public health strategies to encourage outdoor activity and limit excessive screen exposure. Keywords: Stereo acuity, Field vision, Refractive errors, Titmus Fly Test, Depth Perception, Random Dot Stereo Test