How does accent affect the identification of Speech Sound Disorders in Scottish-English speaking children?

Speech Sound Disorders (SSDs) are highly prevalent, affecting up to 25% of children in the UK. In Scotland there have been recent sound changes whereby coronal consonants are replaced with non-coronal consonants. These sound-changes have the potential to be misinterpreted as errors. It is important to investigate whether this variation impacts the identification of SSDs and if current assessment tools account for accent variation. The recommended assessment in the UK is the Diagnostic Evaluation of Articulation and Phonology (DEAP) (Dodd, 2002). This assessment was standardised on UK children, including some from Scotland. However, the manual instructions do not specify which accent features are considered in the scoring of the assessment.

This study used data collected for the VariCS project (VariCS, 2024), which investigated the variability in children`s speech in Scotland. The DEAP diagnostic screen was administered to 275 children (aged 5-12 years) in Scottish schools. Recordings were phonetically transcribed, and errors categorised as age-appropriate or not, according to manual instructions. Phonological and accent features present in the sample were recorded and a comparison made with the DEAP norms.

Initial analysis shows that 45/275 children had speech errors. Errors included: cluster reduction, coalescence, gliding, backing, stopping, deaffrication, affrication, dental fronting, consonant elision and syllable elision. Sociophonetic features included glottalization of /t/ and derhoticisation of post-vocalic /r/.

In further analysis we will evaluate levels of variation in children’s speech and determine how these sound-change variants might be differentiated from developmental errors in children speaking Scottish English. The findings will be used to develop a clinically-useful list of typical sound variants clinicians can expect to encounter in Scottish-English child speech.