Analysis of colour vision with the Ishihara test: A comparison between two groups of subjects with different age range

In the present study, we have described and compared both the number and the types of the mistakes that were made during reading of the Ishihara plates by 3,926 students attending the secondary schools in the province of Cosenza (Calabria, Southern Italy) and by 546 Calabrian university students all without colour-blindness. There were no qualitative differences in the types of mistakes made by the two groups of subjects during their reading of the Ishihara plates. Moreover, we have reported both the mean frequencies and types of colour-blindness in only the province of Cosenza. During this study, it was shown that the ishihara test is reliable during screenings for the diagnosis of colour vision deficiencies, as shown by some previous investigations.