Testing of colour vision for vocational purposes.

All red-green defects of colour vision can be effectively screened with a combination of two pseudo- isochromatic tests. Severe (major) colour vision defects regarded as a serious handicap in all occupations needing colour naming ability can be quickly detected with the Panel D-15 dichotomous test. Only a trained ophthalmologist can make the detailed estimation of the type and degree of the colour vision defect with the aid of the anomaloscope and the Farnsworth-Munsell 100-hue test. In the diagnosis of a congenital colour vision defect the exclusion of an eye disease with a consecutive acquired colour vision defect is important.