Purpose: Traditional normative values of binocular vision, known as Morgan’s & Scheiman’s and Optometry Extension Program(OEP) expected findings, have been used since long in clinical optometry. However, with technological advances, visual habits and visual demands have changed. Therefore, clinical assessment could examine the applicability of the established criteria in Taiwan.
Methods: Participants aged 15–24 years were recruited from three universities and colleges. After completing the Visual Behavioral Performance questionnaire with four components: near work, visual perception, visual comfort and balance of body, participants were separated into symptomatic or asymptomatic groups based on the results of the questionnaire survey. A 24-step binocular visual examination was undertaken. Data were analyzed with the one-sample t-test and an ROC curve to compare and establish normative values for Taiwanese young adults.
Results: Among the 308 healthy Taiwanese young adults, the prevalence of accommodation or vergence anomalies was 15% (46 participants). The commonest dysfunctions in this study were accommodative excess and convergence excess. Most of the binocular visual functions in this study showed significant difference from the traditional normative values: amplitude of accommodation, base-in prism to break and recovery points at distance were better than the traditional normative values, whereas others were worse. In addition, different visual tasks require different binocular visual functions, and the ROC curve was used to analyze the normative values of binocular visual functions required for near work, visual perception, visual comfort, and body balance.
Conclusion and Discussion: The mean values of binocular visual function in Taiwanese young adults were worse than that in the traditional normative values. With changing times, racial differences, and more tasks for visual needs, it is essential to establish binocular visual normative values for Taiwanese young adults.