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Failure of concordance of the Farnsworth D15 test and the Nagel anomaloscope matching range in anomalous trichromatism

Published online by Cambridge University Press:  03 July 2008

JENNIFER BIRCH
JENNIFER BIRCH*
Affiliation:
Henry Wellcome Laboratories, Applied Vision Research Centre, City University, London, United Kingdom
*
Address correspondence and reprint requests to: Jennifer Birch, Henry Wellcome Laboratories, Applied Vision Research Centre, City University, London EC1V OHB, UK. E-mail: [email protected]
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Abstract

The Farnsworth D15 test (D15) was developed for use in occupational guidance. People with significant color deficiency, including all dichromats are expected to fail and people with slight color deficiency are expected to pass. Pass is a circular results diagram and fail an interlacing pattern with one or more red-green isochromatic errors (Farnsworth, 1947). The Nagel anomaloscope is a “gold standard” reference test for identifying and classifying red-green color deficiency. The matching range on the red/green mixture scale indicates the severity of the discrimination deficit. Pass/fail results for the D15 are presented for 107 protanomalous and 410 deuteranomalous trichromats and compared with the anomaloscope matching range. Thirty-six percent of the subjects examined failed the D15. Protanomalous trichromats are able to utilize perceived luminance contrast to obtain good results on the D15 but 42% of these subjects failed the D15 compared with 35% of deuteranomalous subjects. Failure of the D15 was clearly related to the Nagel matching range in deuteranomalous trichromatism but not in protanomalous trichromatism. For example, 84% of deuteranomalous subjects with matching ranges > 30 scale units failed the D15 but only 2% with matching ranges < 9 scale units were unsuccessful. In comparison, 53% of protanomalous subjects with matching ranges > 15 scale units and 33% of subjects with matching ranges < 5 scale units were unsuccessful. Protanomalous trichromats with apparently minimal color deficiency are therefore shown to have poor practical hue discrimination ability as measured with this test.

Keywords

Anomalous trichromatsD15Nagel anomaloscope
Type
Research Article
Information
Visual Neuroscience , Volume 25 , Issue 3 , May 2008 , pp. 451 - 453
Copyright
Copyright © Cambridge University Press 2008

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References

REFERENCES

Barbur, J.L., Harlow, A.J. & Plant, G.T. (1994). Insights into the different exploits of colour in the visual cortex. Proceedings of the Royal Society (London) B: Biological Science 258, 327–334.Google ScholarPubMed
Barbur, J.L., Rodriguez-Carmona, M.L. & Harlow, A.J. (2005). The relative merits of anomaloscope matches and colour discrimination tests in assessing loss of chromatic sensitivity. Abstract: Meeting of the Optical Society of America, Tucson.Google Scholar
Barbur, J.L., Rodriguez-Carmona, M.L., Harlow, J.A., Mancuso, K., Neitz, J. & Neitz, M. (2008). A study of unusual Rayleigh matches in deutan deficiency. Visual Neuroscience 25, 507–516.CrossRefGoogle ScholarPubMed
Birch, J. (1982). Diagnosis of defective colour vision with the Nagel anomaloscope. In Documenta Ophthalmologica Proceedings Series 33, ed. Verriest, G., pp. 231–235. The Hague, Netherlands: Junk.Google Scholar
Birch, J. (1997). Efficiency of the Ishihara test for identifying red-green colour deficiency. Ophthalmic and Physiological Optics 17, 403–408.CrossRefGoogle ScholarPubMed
Birch, J. (2003). Extreme anomalous trichromatism. In Normal and Defective Color Vision, ed. Mollon, J.D., Porkorny, J. & Knoblauch, K., pp. 364–369. Oxford, UK: Oxford University Press.CrossRefGoogle Scholar
Birch, J. (2008). Pass rates for the Farnsworth D15 Colour Vision test. Ophthalmic and Physiological Optics 23, 259–264.CrossRefGoogle Scholar
CIE. (2001). International Recommendations for Colour Vision requirements in Transport. Report No.143. CIE Vienna, Austria.Google Scholar
Cole, B.L. (2007). Assessment of inherited colour vision defects in clinical practice. Clinical and Experimental Optometry 90, 157–175.CrossRefGoogle ScholarPubMed
Farnsworth, D. (1947). The Farnsworth Dichtotomous Test for Colour Blindness Panel D15 Test Manual. New York: Psychological Corporation.Google Scholar
He, J.C. & Shevell, S.K. (1995). Variations in colour matching and discrimination among deuteranomalous trichromats: Theoretical implications of small differences in photopigments. Vision Research 35, 2579–2588.CrossRefGoogle ScholarPubMed
Jagla, W., Breitspecher, T., Kucsera, I., Kovacs, G., Wissinger, B., Deeb, S.S. & Sharpe, L.T. (2003). Hybrid pigment genes, dichromacy and anomalous trichromacy. In Normal and Defective Colour Vision, ed. Mollon, J.D., Pokorny, J. & Knoblauch, K., pp. 307–317. Oxford, UK: Oxford University Press.CrossRefGoogle Scholar
Margrain, T.H., Birch, J. & Owens, C.G. (1996). Colour vision requirements of firefighters. Occupational. Medicine. (London) 46, 114–124.CrossRefGoogle ScholarPubMed
McKeon, W.M. & Wright, W.D. (1940). The characteristics of protanomalous vision. Proceedings of the Royal Society (London) 52, 464–479.CrossRefGoogle Scholar
Paulson, H.M. (1973). Comparison of color vision tests used in the armed forces. In Color Vision, ed. Judd, D.B., pp. 34–64. Washington, DC: National Academy of Science.Google Scholar
Rodriguez-Carmona, M.L., Harlow, A.J., Walker, G. & Barbur, J.L. (2005). Variability of normal trichromatic vision and the establishment of the normal matching range. Proceedings of the 10th Congress of the Association Internationale de la Couleur (AIC), Granada, Spain, pp. 979–982.Google Scholar
Shevell, S.K., He, J.C., Kainz, P., Neitz, J. & Neitz, M. (1998). Relating color discrimination to photopigment genes in deutan observers. Vision Research 38, 3371–3376.CrossRefGoogle ScholarPubMed
Thomas, P.B.M. & Mollon, J.D. (2004). Modelling the Rayleigh match. Visual Neuroscience 21, 477–482.CrossRefGoogle ScholarPubMed