Task factors contribute to dyslexics’ difficulties with tests of phonological awareness

Task factors contribute to dyslexics’ difficulties with tests of phonological awareness

First Author: Pierre Cormier -- Universite de Moncton
Additional authors/chairs: 
Stacy Corbin
Keywords: Phonological awareness, Dyslexia, Testing, French
Abstract / Summary: 

Developmental dyslexics score lower on tests of phonemic awareness than typically developing children (Melby-Lervåg et al., 2012). Yet many factors may be involved in those tests, including the position of the phoneme in the word (McBride-Chang, 1995), the type of phoneme (Chafouleas et al., 2001), whether the target is word or not (Farquharson et al., 2014), etc. In this study, we recorded a large number of variations in the items composing a test of phonological awareness involving deletion of either a syllable or a phoneme. These variations included all types of consonant phonemes (6) in the language, French, whether the phonemes were sonorous or not, the type of phonological unit, syllable or phoneme, the position of the phonological unit in the word, whether the phonemes were isolated or within a consonant blend, whether the answer was a word or not, etc.
A stepwise discriminant analysis was carried out to uncover which subset of the 8 variables representing phonetic characteristics and 14 item descriptors distinguished 17 dyslexics (11 in grade three and 6 in grade five) from 42 typically developing children (26 in grade three and 16 in grade 5). Dyslexics were weaker than typically developing children on all types of phoneme characteristics, all F’s (1, 54) > 11.00, p’s < .001. The discriminant function classified successfully 98% of all children, classifying correctly all 15 dyslexics and representing only one normal reader as a dyslexic. Four variables contributed to this classification, two phonetic variables, the palatal-velar and the uvular items, and two item descriptors, the total score on phonemes and the lexicality effect (whether the answer was a word or not).
In this examination of the factors affecting performance on a task of phonological awareness, dyslexics had more difficulties than typically developing children on all factors, suggesting a general deficit consistent with the phonological core deficit hypothesis (Stanovich, 1988).