Early speech sound disorder (SSD) combined with other risk factors, such as language impairment (LI) and dyslexia, can have negative consequences on literacy development, according to new research from Marianna Hayiou-Thomas and colleagues. The researchers screened a cohort of 245 children for SSD at age 3.5 years using the Diagnostic Evaluation of Articulation and Phonology.
A total of 68 children with SSD were identified, of which >50% still exhibited SSD at age 5.5 years. The children completed assessments for literacy skills based on measures of phoneme (language sounds) awareness, word-level reading, spelling and reading comprehension at age 5.5 and 8 years. Those with SSD showed weak emergent literacy skills compared to typically developing controls in terms of phonemic skills at age 5.5 years and word reading at age 8 years. When subdividing those with SSD according to co-occurring conditions, children with isolated SSD showed problems in literacy only at age 3.5 years thus suggesting that poor literacy due to SSD alone is short-lived and has only a modest effect on literacy development. Those with SSD and LI, however, showed worse literacy skills than those with SSD alone at ages 5.5 and 8 years, and this effect was even more pronounced in those also at familial risk of dyslexia.
The researchers advise that clinicians should monitor children through the early stages of literacy development if they have SSD and a family risk of dyslexia or a co-occurring LI.
Hayiou-Thomas, M.E., Carroll, J.M., Leavett, R., Hulme, C. & Snowling, M.J. (2017), When does speech sound disorder matter for literacy? The role of disordered speech errors, co-occurring language impairment and family risk of dyslexia. J Child Psychol Psychiatr. 58: 197-205. doi:10.1111/jcpp.12648
Speech sound disorder (SSD): A persistent difficulty with speech sound production that interferes with speech intelligibility or prevents verbal communication. Symptoms first emerge in early childhood and are not attributable to congenital or acquired conditions. Affected children make systematic omissions, substitutions or distortions of phonemes within words, despite being able to repeat these phonemes in isolation.