The Cardiff Acuity Test is designed especially for the hard-to-test age group, 12 months to 3 years. It uses familiar pictures and a procedure in the form of a game to attract and keep the attention of young children. However, the test does not require the child to be able to name or even to recognise the pictures. Instead, it relies on the technique of ‘preferential looking’ – that is, the observer simply notes the child’s eye movements in order to determine whether he or she can see the picture.

This means that that the test can be used irrespective of a child’s developmental stage, making it ideal for testing children and adults with intellectual disabilities.The Cardiff Acuity test was developed by Dr. J. Margaret Woodhouse, at the School of Optometry and Vision Sciences, Cardiff University, UK. It has been rigorously validated, and is now recommended by leading paediatric vision consultants worldwide.

The Cardiff Acuity Test has been recently relaunched, and is now available in two versions. The standard version covers a range of visual acuity levels from 6/48 and 6/96 to 6/3.75 and 6/7.5 (at working distances of 1 metre and 50 cm). The Low Vision version, aimed at practitioners working in the field of visual impairment, covers 6/96 and 6/192 to 6/7.5 and 6/15, at the same working distances. Both versions test visual acuity in steps of one-third octave, or 0.1 logMAR, thus offering good precision in measurement.

The test is portable, comes with its own carry-case and full instructions.