Phonologic performance profiles of dyslexic versus non-dyslexic students : a case study

Abstract

The main goal of this comparative research study was to investigate for any differences that were likely to prevail between a group of dyslexic students (n = 9, μ = 10.08, σ = ± 0.70) and their non-dyslexic counterparts (n = 7, μ = 9.93, σ = ± 0.54), in terms of basic abilities attributable to language acquisition, phonemic awareness, grapheme to phoneme conversion, level of comprehension and responsiveness, reading performance and semantic memory. Standard National screening word spelling and reading tests, including the Macmillan Graded Word Reading Test (NFER-Nelson, 1985) were used. Results obtained for the Maltese spelling test revealed that the dyslexic (D) group fared badly when compared with the non-dyslexic (non-D) group in respect of the spelling age ( μ(D)7.14 ± 0.81< μ (non-D) 95±1.15 ), raw score ( μ (D)47.71± 13.47< μ (non-D ) 23.11± 13.68), and standardized score (μ(D) =70.01± 8.< μ (non-D) 90.43± 11.73); denoting that the phonological impairment was quite significant in dyslexia. Comparable results were obtained for the English spelling test in respect of spelling age (μ (D) 7.2 ± 0.69< μ (non-D) 10.00± 1.70), raw score (μ (D) = 23.89±12.6 < μ (non-D) = 54.71± 15.45), and standardized score (μ (D) =72.11± 7.22 < μ (non-D) 98±12.11). In case of both Maltese and English spelling, errors for omission and substitution were significantly higher in dyslexia, indicating that a phonological deficit may be the over-riding factor. The reading tests provided even more insights about the attributes and levels of skill performance characterizing dyslexic versus non-dyslexic participants. The sight vocabulary percentage scores obtained for the dyslexic group were relatively lower compared to the control group. For Maltese reading, the mean percentage sight vocabulary for the dyslexic group was: (μ (D) 71.4% ± 16.1% < μ (non-D) = 81.8%± 12.6%); whereas for the English reading test the mean for dyslexic group was: (μ (D) =67.7% ± 10.6% <μ (non-D) =77.4% ± 10.90%). Reading errors recorded included mispronunciations and to a lesser extent reversals, indicating that auditory or phonological deficits were particularly predominant.