A calculation and number processing battery for clinical application in illiterates and semi-literates.

Ten simple tasks assessing counting, number processing, elementary calculation and quantity estimation were proposed to 122 normal Brazilian adults aged between 18 and 58 years with 0, 1, 2, 3 or 4 years of education. Tasks such as counting the number of elements in small sets were almost perfectly mastered by these illiterate or semi-literate normal subjects; however in other tasks (e.g. those assessing knowledge of the correspondence between numbers and banknotes) a sizeable proportion of the sample showed errors. The pattern of errors was analysed to identify difficulty factors. A strong gender effect with better performance in men than women was observed, which was even greater than the expected effect of educational level. Results in normals allowed to propose cut-off scores for neuropsychological assessment in brain-damaged patients with very low levels of education, which were tested in a small sample of illiterate or semi-literate patients with cerebrovascular accident. It is argued that the relatively neglected area of neuropsychological assessment in illiterates is of great practical and theoretical interest.