Deficient colour vision and interpretation of histopathology slides: cross sectional study.

Abstract

To determine whether histopathologists with deficient colour vision make more errors in slide interpretation than those with normal colour vision. Examination of projected transparencies of histopathological slides under standardised conditions by subjects whose colour discriminating ability was accurately assessed. Departments of histopathology in 45 hospitals in the United Kingdom. 270 male histopathologists and medical laboratory scientific officers. Number of slides correctly identified by subjects whose colour vision was measured on the Ishihara, City University, and Farnsworth-Munsell 100 hue tests. Mean (SD) scores (out of 10) for doctors with colour deficient vision were 9.4 (0.7) v 9.9 (0.4) for controls (P < 0.01) and 7.5 (1.6) v 9.4 (0.7) for scientific officers (P < 0.001). When subjects with colour deficient vision were categorised into severe, moderate, or mild, there was a significant trend towards those with severe deficiency making more mistakes (P < 0.001). Histopathologists and medical laboratory scientific officers should have their colour vision tested; if they are found to have a severe protan or deutan deficiency, they should be advised to adopt a safe system of working.