How many words make a sample? Determining the minimum number of word tokens needed in connected speech samples for child speech assessment

The Relationship Between Speech Accuracy and Linguistic Measures in Narrative Retells of Children With Speech Sound Disorders

BACKGROUND

Speech and language are interconnected systems, and language disorder often co-occurs with childhood apraxia of speech (CAS) and non-CAS speech sound disorders (SSDs). Potential trade-off effects between speech and language in connected speech in children without overt language disorder have been less explored.

METHOD

Story retell narratives from 24 children (aged 5;0-6;11 [years;months]) with CAS, non-CAS SSD, and typical development were analyzed in Systematic Analysis of Language Transcripts (SALT) regarding morphosyntactic complexity (mean length of C-unit in words [MLCU]), lexical diversity (moving-average type-token ratio [MATTR]), and linguistic accuracy (any linguistic error/bound morpheme omissions) and compared to 128 age-matched children from the SALT database. Linear and mixed-effects logistic regressions were performed with speech accuracy (percent phonemes correct [PPC]) and diagnostic group as predictors of the narrative variables.

RESULTS

PPC predicted all narrative variables. Poorer PPC was associated with lower MLCU and MATTR as well as a higher likelihood of linguistic errors. Group differences were only observed for the error variables. Comparison to the SALT database indicated that 13 of 16 children with CAS and SSD showed a higher-than-expected proportion of linguistic errors, with a small proportion explained by individual speech errors only.

CONCLUSIONS

The high occurrence of linguistic errors, combined with the relationship between PPC and linguistic errors in children with CAS/SSD, suggests a trade-off between speech accuracy and language output. Longitudinal studies are needed to investigate whether children with SSDs without language disorder show more language difficulties over time as linguistic demands increase.

Research Priorities for Childhood Apraxia of Speech: A Long View

This article introduces the Journal of Speech, Language, and Hearing Research Special Issue: Selected Papers From the 2022 Apraxia Kids Research Symposium. The field of childhood apraxia of speech (CAS) has developed significantly in the past 15 years, with key improvements in understanding of basic biology including genetics, neuroscience, and computational modelling; development of diagnostic tools and methods; diversity of evidence-based interventions with increasingly rigorous experimental designs; and understanding of impacts beyond impairment-level measures. Papers in this special issue not only review and synthesize the some of the substantial progress to date but also present novel findings addressing critical research gaps and adding to the overall body of knowledge. A second aim of this prologue is to report the current research needs in CAS, which arose from symposium discussions involving researchers, clinicians, and Apraxia Kids community members (including parents of children with CAS). Four primary areas of need emerged from discussions at the symposium. These were: (a) What questions should we ask? (b) Who should be in the research? (c) How do we conduct the research? and (d) How do we move from research to practice? Across themes, symposium attendees emphasized the need for CAS research to better account for the diversity of people with CAS and improve the timeliness of implementation of high-level evidence-based practice across the lifespan. It is our goal that the articles and prologue discussion in this special issue provide an appreciation of advancements in CAS research and an updated view of the most pressing needs for future research.