Cross-national comparisons of developmental dyslexia in Italy and the United States.

This study was designed to examine whether the phonetic regularity of a language can significantly influence the prevalence and pattern of developmental dyslexia. Demographically matched samples of fifth-grade children in Italy (N = 448) and the United States (N = 1,278) were evaluated to identify children with specific reading disabilities. Reading disabled children with average intelligence were compared to normal controls on a series of neuropsychological tests to evaluate specific cognitive deficits associated with reading disorders in each country. The findings suggested that (a) dyslexia is more prevalent in the United States than in Italy, (b) reading disabilities are strongly associated with disorders of verbal processing in both countries, although some American dyslexics also show visual-motor deficits, and (c) there is a greater dissociation between reading comprehension and decoding in Italian than in English.