A potential new colour vision assessment tool for young children

Abstract

Aim: There are many colour vision tests available that detect, classify and grade colour deficiency for adults. Testing colour vision in older children is possible using the same tests but very young children may not yet be confident in identifying pictures and numerals, or may not understand tracing coloured pathways. This pilot study was designed to assess whether Lego1 bricks, which are available in many waiting areas, could be applied to detect colour vision deficiency. Methods: Two groups of 10 male subjects (age 18–32 years) were recruited. One group were colour normal (CVNorm) and 10 were aware of a colour defect (CVDef). Each group completed a standard colour vision assessment consisting of the anomaloscope, Ishihara pseudo-isochromatic plates and D-15 saturated caps. The CVNorm and CVDef groups were required to match Lego1 bricks of the same colour from a tray containing bricks of many colours within a light box using standard illuminant C. Different numbers of the test bricks (red, green, blue, yellow and beige) were randomly selected. Black, light green, white and orange bricks were added as distraction bricks. In a given time limit subjects had to select the bricks of a colour chosen by the assessor, and were scored for incorrectly chosen or missed bricks. The task was repeated under fluorescent and incandescent illumination. Results: CVNorm subjects had zero errors matching the bricks under all three illumination conditions. The CVDef group consisted of 9 dichromats (6 deuteranopes, 3 protanopes) and 1 deuteranomalous trichromat. Some CVDef subjects made one or two errors but in general many completed the task without making any errors. There was no statistical difference between the groups under any of the three illumination conditions. Conclusion: Conventional Lego1 bricks did not detect colour-matching problems in adults previously identified with severe colour deficiency and therefore cannot be recommended as a single test for paediatric colour vision examination.

Keywords

• Anomaloscope
• Colour vision
• Farnsworth D15 test
• Ishihara plates