Relationship between Status of Phoria with CISS and Refractive Error
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Abstract
Aim: To evaluate the relationship between phoria status, Convergence Insufficiency Symptom Survey (CISS) score, and refractive error.
Settings and design: Prospective, Institution-based cross-sectional study.
Methods and materials: Conducted at ITM Skills University, Navi Mumbai (September 2024–April 2026), involving 100 students. Data included refractive status, binocular vision assessment, and CISS responses. Non-parametric tests were applied due to non-normal data distribution.
Results: Mean age was 19.34 ± 1.22 years. Emmetropia (59%) was most common, followed by myopia (39%) and hyperopia (2%). Orthophoria predominated at distance and near. Mean CISS score was 12.85 ± 9.83 with Median = 10 and IQR = 12 (Q1 = 6, Q3 = 18). MSE showed a significant positive correlation with CISS score (rho = 0.296, p = 0.003). Spearman’s correlation showed a weak negative association between distance phoria score and mean spherical equivalent (ρ = −0.202, p = 0.044), whereas categorical analyses using Chi-square showed no significant association between distance phoria and refractive-status group (χ² = 8.72, df = 4, p = 0.069).
Conclusion: Refractive error, phoria status, and symptoms showed weak associations, highlighting the importance of comprehensive binocular vision assessment.
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