Spelling impairments in Italian dyslexic children: phenomenological changes in primary school

Introduction: Although spelling difficulties are constantly associated with developmental dyslexia, they have been largely neglected by the majority of studies in this area. This study analyzes spelling impairments in developmental dyslexia across school grades in Italian, a language with high grapheme-to-phoneme correspondence. Methods: The performances of 33 Italian dyslexic children attending Grades 3 and 5 were compared with those of age-matched control participants. Writing abilities were investigated through a spelling test that included regular words with one-sound-to-one-letter correspondence, regular words requiring the application of context-sensitive conversion rules, words with unpredictable transcription and nonwords with one-sound-to-one-letter correspondence. Results: Both accuracy and error analyses indicate that the spelling impairment assumes different characteristics at different grades: Grade 3 children showed an undifferentiated spelling deficit (involving regular words, regular nonwords and words with unpredictable spelling), whereas the fifth graders were prevalently impaired in writing words with unpredictable transcription. The error analysis confirms these results, with third graders producing a high rate of all types of errors (i.e., phonologically plausible, simple and context-sensitive conversion errors), whereas most errors committed by fifth graders were phonologically plausible. Conclusions: Results are coherent with the hypothesis that dyslexic children learning a shallow orthography suffer from delayed acquisition and some fragility of the sub-word level routine, together with a severe and long-lasting deficit of orthographic lexical acquisition.