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OBJECTIVES: To assess whether results obtained by Titmus V4 occupational landolt model are valid compared to the results obtained by traditional vision tests. MATERIAL AND
METHODS: Specific tests were performed by Titmus for distance and near visual acuity, stereoacuity and color perception while traditional vision tests were performed by using 20-feet and 14-inch number snellen charts for visual acuity, Stereofly wirt dot for stereoacuity and Ishihara 38-plates for color perception.The results obtained through Titmus and those obtained through traditional vision tests were compared. Descriptive statistics, sensitivity, specificity and kappa statistics were calculated for data analysis.
RESULT: Visual performance of 220 participants mean aged 34 ± 8.6 years was obtained. Sensitivity of Titmus for distance visual acuity, near visual acuity, color perception and stereoacuity were 95.8%, 90.9%, 100% and 64.3% respectively. Specificity of Titmus for distance visual acuity, near visual acuity, color perception and stereoacuity were 64.8%, 61.7%, 100% and 68.2% respectively. Agreements of Titmus ranged from 63.2% (Near VA Both eyes) to 100% (color perception.)
CONCLUSION: Titmus proved to be a valid test for color vision deficiency. Titmus can also be used as an occupational vision screener for the assessment of distance and near visual acuity, but with poor diagnostic criteria. According to Titmus’s moderate sensitivity and specificity, Titmus is not suggested to be used for stereoacuity test. It is recommended that further clinical investigation to be undertaken for a more accurate diagnosis of the extent of abnormal visual performance among those whose tests are positive for Titmus.
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