Color DX – Evaluation of Colour Deficiencies
Pseudo-isochromatic colour vision test that uses numbers and shapes (circle, star, cross and square) to make colour vision testing possible from as young as 36 months old.
It replaces the CVTE with one comprehensive test for all ages. It comprises 24 testing plates in total, plus two demonstration pages. Clear instructions are printed in the book.
The 17- page Numbers Test screens for red/green colour deficiency in the first 14 plates. Plate 15 estimates the type (Protan, Deutan) and strength of the deficiency, and plates 16 and 17 screen for any blue deficiency (Tritan).
The shapes section comprises 7 testing pages, plus a demonstration plate. Six pages screen for red/green deficiency, and plate 7 screens for blue deficiency. Results are easily scored on a form to indicate a pass or fail
Ideal distance for conducting the test is 16″ to 24″ (40-60 cm) from the patient’s eyes. The test surface must be perpendicular to the line of sight.