Objective: To determine the prevalence of heterophoria at distance and near and to analyze associated factors among students of the Vietnam Military Medical University (VMMU).
Subjects and Methods: A cross-sectional descriptive study was conducted on 261 students. All participants underwent comprehensive ophthalmic examinations, including visual acuity testing, refraction, and heterophoria evaluation at distance and near. Heterophoria was primarily detected using the alternate cover test. Associated factors investigated included refractive errors, duration of electronic device use, academic year, and ocular symptoms. Data were analyzed using STATA software with appropriate statistical tests and multivariable logistic regression.
Results: The prevalence of distance heterophoria was 18.01%, with exophoria predominating (17.24%) and esophoria accounting for a small proportion (0.77%). At near fixation, the prevalence of heterophoria increased to 45.59%, mainly exophoria (44.06%). Multivariable logistic regression analysis identified refractive errors and headache/eye-strain symptoms as independent risk factors.
Conclusion: Heterophoria, particularly near exophoria, was relatively common among students of the Vietnam Military Medical University. This condition was closely associated with refractive errors, headache, and eye strain symptoms.