Assessing students with colour blindness or colour discrimination problems
Two of the CoPS subtests – Crayons and Toybox (under 7 years version only) – specifically rely on colour perception for the student’s response. Obviously if the student scores poorly on these subtests it could be because of colour blindness or some other colour discrimination difficulty. Indeed, if the student performs poorly on either of these two subtests, it is recommended that the student should be given the supplementary subtest Clown in order to check for problems of colour discrimination. In the remaining subtests in CoPS, although colour is employed, it is not central to the task, and colour blindness or colour discrimination difficulties should not affect performance.
Teachers sometimes ask whether knowing the names of the colours helps students to complete Crayons and Toybox. However, whether they do or do not know colour names, these subtests are still valid because they were found to be predictive of later literacy difficulties without reference to knowledge of colour names. Teaching the students colour names specifically for the purposes of attempting these subtests is not recommended, because students who have only just acquired the names of the colours and not begun to use them fluently might be more liable to confusion. Some students clearly use the labels for the colours as a verbal strategy in these subtests, but this does not seem to be the case with all students – it appears to be possible to do these subtests using only visual strategies.