Speech production accuracy in children with Down syndrome: relationships with hearing, language, and reading ability and change in speech production accuracy over time

Background - This study examines speech production accuracy in children with Down syndrome and concurrent relationships with hearing, language and reading ability. It also examines change in speech production accuracy over a 21-month period.

Methods - A group of 50 children with Down syndrome (aged 5–10 years) completed measures of speech accuracy, non-verbal IQ, reading (single-word reading, letter–sound knowledge and phoneme blending) and language (expressive and receptive vocabulary and receptive grammar). Hearing was assessed by parental report. Speech accuracy was reassessed 21 months later.

Results - Although there was considerable variability in the sample, speech was characterised by high levels of errors. There were no effects of gender, hearing status or non-verbal IQ on speech production accuracy. In contrast, speech production accuracy was significantly related to age and to measures of receptive vocabulary, phoneme blending and word reading. There was no significant improvement in speech production accuracy over time.

Conclusions - Children with Down syndrome experience difficulties producing accurate sounds in speech. These difficulties are related to age and to vocabulary and reading skills and persist over time, highlighting the need for intensive targeted speech intervention in this group of children.