Ocular dominance and its association with handedness among medical undergraduates: A cross-sectional study

Abstract

Background: Despite the symmetry of the body, there is an inherent preference for the parts of one side of the body over the other. It is apparent in the hands. In addition to hand preference, there is also preference for the visual input of one eye over the other. The preferred eye is known as dominant eye or ocular dominance. Aim and Objective: This study aims to determine the association between handedness and ocular dominance among medical undergraduates. Materials and Methods: A cross-sectional study included one hundred 2nd year medical undergraduates of 19–21 years of age. Informed consent from the participants and Institutional Ethical Clearance were obtained. Hand preference was determined using Edinburg Handedness Inventory. Ocular dominance was tested by Miles test. Data obtained were statistically analyzed. Results: About 82% of subjects were right handed and 18% left handed. By Miles test, 76% were right eye dominant and 24% were left eye dominant. On cross-tabulation, 19.5% right handed were left eye dominant and 55.6% left handed were right eye dominant. About 74% showed uncrossed hand ocular dominance and 26% showed crossed dominance (Chi-square value = 5.03, df = 1, P = 0.03). Conclusion: Study showed significant association between dominant hand and dominant eye wherein 26% of subjects showed crossed dominance. Evaluating eye hand dominance or crossed dominance might be helpful to assess learning difficulties and also helpful to young players or athletes that allow them to choose whether to hit with their left or right hand or to swap hits. This is a crucial topic for laterality research in the future.