The ninth subtest (Clown) was added to CoPS in order to identify students with poor colour discrimination or colour ‘blindness’. This is not because colour discrimination is a predictor of literacy attainment, but because performance on two CoPS tests (Crayons and Toybox) may be affected by poor colour discrimination. Approximately 7.5% of males and less than 1% of females are colour blind, which reflects a sex-linked recessive inheritance. The colour discriminations tested in Clown are:
- Light Blue
- Dark blue
These are the colours used in Toybox and Crayons. Of these colours, the most likely confusion in a student who is colour blind will be when trying to distinguish red and green.
The task is to paint sections of the clown with the colours indicated, by selecting the appropriate coloured paint tube in the row at the bottom of the screen – the range of colours in this display changes each time. Clown may be regarded as a supplementary subtest (rather than a core subtest). In cases where students have scored low on either Crayons and/or Toybox, Clown should be administered; otherwise it is optional. However, because Clown is a very easy subtest for most students to do, many teachers use it as an introduction to the CoPS subtests, especially for younger students in the age range.
Figure 28. ‘Paint the clown’