R 298
Vision testing in driving licencing results of an European Community study
H. Wilhelm1, S. Heine1, D. Gamer1, S. Kuske1, S. Nitsch3, R. Kaper2, M. Emesz3, R. van Rijn2, G. Grabner3
A test procedure will only be accepted if its results reflect the subjectively perceived disability at least to some extent. A test which is passed by most of those who feel disabled is inacceptable, and the same is true for a test in which a great number of those who dont perceive any major disability will fail. A European multicenter study in Amsterdam, Salzburg and Tübingen examined the relation between perceived disability and test outcome.
Methods: 103 participants elder than 50 years and all car drivers, both normal subjects and patients with media disturbancies, retinal disorders or glaucoma, filled in a questionnaire (National Eye Institute - Visual Functioning Questionnaire, NEI-VFQ-25) providing a disability score. Thereafter visual acuity (EDTRS), photopic (Pelli-Robson-Chart) and mesopic contrast vision (Nyktotest and Mesotest), visual field (Humphrey FA) and Useful Field of View (UFOV) according to Owsley were determined and the morphology was examined. Correlations were calculated by linear regression.
Results: Significant correlation was found between perceived disability and test outcome for visual acuity, photopic contrast vision (strongly related to visual acuity) and UFOV. Close to significant were the mesotest results with and without glare (p = 0.06 and 0.07). Night driving problems correlated well to the Nyktotest device.
Discussion: Visual acuity reflects perceived visual disability of the elderly car drivers surprisingly well. UFOV, which tests not only vision but also concentration, reaction time and skill, creates a very complex test setting and tests the ability to compensate for the visual deficit as well. This test gave the best prediction for the subjective disability. Night driving problems were best recognized by the Nyktotest (high mesopic background) whereas the mesotest (lower mesopic background) better reflected general disability.
1-Universitäts-Augenklinik, Tübingen, Germany
2-Dpt. of Ophthalmology, Univ. Hospital Vrije Universiteit, Amsterdam
3-Landesaugenklinik für Augenheilkunde und Optometrie, Salzburg