Abstract
The main purpose of this study was to inform the development of screening tools for identifying dyslexia in the Persian language. Measures based on those used in English tests were investigated to assess their relevance for Persian-based assessments. Five studies were conducted. In the first, 140 Persian speaking pupils from five different grades were tested to determine the appropriateness of the measures for use across these grades. In the second study, 64 students were examined with more complex test items to reduce ceiling effects in the data. Overall, the results of these studies suggested a high level of accuracy in text reading in early stages of Persian literacy development. Three further studies then contrasted Persian and English, and dyslexic and non-dyslexic, children. Study 3, in which 40 Persian and 50 English pupils in the third and forth year of schooling were tested, revealed consistency in phonological processing predictors of literacy levels across cohorts. Study 4 compared 36 dyslexic and 58 non-dyslexic grade 1 and 2 Persian children and identified deficits among dyslexic children in literacy and phonological processing. Similar conclusions were derived in study 5, which contrasted differences in performance of year 3 English dyslexics (N=23) and non-dyslexics (N=25) with those found with grade 2 Persian dyslexics (N=16) and non-dyslexics (N=30). These results could be argued to be confirmatory of theories of dyslexia that propose a universal (cross-language) phonological deficit as the primary cause of dyslexia amongst children. However, the studies reported in this thesis also indicated that the Persian learners reached higher levels of accuracy earlier than their English counterparts, a finding more consistent with script-dependent viewpoints. The data are discussed in terms of these underlying causes and the implications for practice (assessment and intervention) are considered for this relatively under-studied language.