Data-driven subclassification of speech sound disorders in preschool children

The Relationship between Speech Sound Disorder and Cortical Auditory Evoked Potential

INTRODUCTION

Speech sound disorder (SSD) is a speech and language disorder associated with difficulties in motor production, perception, and phonological representation of sounds and speech segments. Since auditory perception has a fundamental role in forming and organizing sound representation for its recognition, studies that evaluate the cortical processing of sounds are required. Thus, the present study aimed to verify the relation between SSD severity measured by the percentage of correct consonants (PCCs) with the cortical auditory evoked potentials (CAEPs) using speech stimulus.

METHODS

Twenty-nine children with normal hearing participated in this research and were grouped into three groups by SSD level measured by the PCC index. In addition, the groups were subdivided according to the children's age group: between 60-71 months, 72-83 months, and 83-94 months. The CAEP with speech stimulus was carried out in all children.

RESULTS

Older children had longer P1 and N1 latencies. In P2 latency, there was an interference of age only in the severe group. The N2 latency was affected by age, where older children had longer latency.

CONCLUSION

The amplitude of CAEP has not suffered any interference with the age, or severity of SSD. For the latency, older children generally presented longer averages than younger ones.

Predictors of Functional Communication Outcomes in Children With Idiopathic Motor Speech Disorders

PURPOSE

The purpose of the study was to investigate child- and intervention-level factors that predict improvements in functional communication outcomes in children with motor-based speech sound disorders.

METHOD

Eighty-five preschool-age children with childhood apraxia of speech (n = 37) and speech motor delay (n = 48) participated. Multivariable logistic regression models estimated odds ratios and 95% confidence intervals for the association between minimal clinically important difference in the Focus on the Outcomes of Communication Under Six scores and multiple child-level (e.g., age, sex, speech intelligibility, Kaufman Speech Praxis Test diagnostic rating scale) and intervention-level predictors (dose frequency and home practice duration).

RESULTS

Overall, 65% of participants demonstrated minimal clinically important difference changes in the functional communication outcomes. Kaufman Speech Praxis Test rating scale was significantly associated with higher odds of noticeable change in functional communication outcomes in children. There is some evidence that delivering the intervention for 2 times per week for 10 weeks provides benefit.

CONCLUSION

A rating scale based on task complexity has the potential for serving as a screening tool to triage children for intervention from waitlist and/or determining service delivery for this population.

Using ultrasound tongue imaging to support the phonetic transcription of childhood speech sound disorders

This study aims to determine whether adding an additional modality (ultrasound tongue imaging) improves the inter-rater reliability of phonetic transcription in childhood speech sound disorders (SSDs) and whether it enables the identification of different or additional errors in children's speech. Twenty-three English speaking children aged 5-13 years with SSDs of unknown origin were recorded producing repetitions of /aCa/ for all places of articulation with simultaneous audio and ultrasound. Two types of transcriptions were undertaken off-line: (1) ultrasound-aided transcription by two ultrasound-trained speech-language pathologists (SLPs) and (2) traditional phonetic transcription from audio recordings, completed by the same two SLPs and additionally by two different SSD specialist SLPs. We classified transcriptions and errors into ten different subcategories and compared: the number of consonants identified as in error by each transcriber; the inter-rater reliability; and the relative frequencies of error types identified by the different types of transcriber. Results showed that error-detection rates were different across the transcription types, with the ultrasound-aided transcribers identifying more errors than were identified using traditional audio-only transcription. Analysis revealed that these additional errors were identified on the dynamic ultrasound image despite being transcribed as correct, suggestive of subtle motor speech differences. Interrater reliability for classifying the type of error was substantial (κ = 0.72) for the ultrasound-aided transcribers and ranged from fair to moderate for the audio-only transcribers (κ = 0.38 to 0.52). Ultrasound-aided transcribers identified more instances of increased variability and abnormal timing errors than the audio-only transcribers.

Process-Oriented Profiling of Speech Sound Disorders

The differentiation between subtypes of speech sound disorder (SSD) and the involvement of possible underlying deficits is part of ongoing research and debate. The present study adopted a data-driven approach and aimed to identify and describe deficits and subgroups within a sample of 150 four to seven-year-old Dutch children with SSD. Data collection comprised a broad test battery including the Computer Articulation Instrument (CAI). Its tasks Picture Naming (PN), NonWord Imitation (NWI), Word and NonWord Repetition (WR; NWR) and Maximum Repetition Rate (MRR) each render a variety of parameters (e.g., percentage of consonants correct) that together provide a profile of strengths and weaknesses of different processes involved in speech production. Principal Component Analysis on the CAI parameters revealed three speech domains: (1) all PN parameters plus three parameters of NWI; (2) the remaining parameters of NWI plus WR and NWR; (3) MRR. A subsequent cluster analysis revealed three subgroups, which differed significantly on intelligibility, receptive vocabulary, and auditory discrimination but not on age, gender and SLPs diagnosis. The clusters could be typified as three specific profiles: (1) phonological deficit; (2) phonological deficit with motoric deficit; (3) severe phonological and motoric deficit. These results indicate that there are different profiles of SSD, which cover a spectrum of degrees of involvement of different underlying problems.

Characterizing sensorimotor profiles in children with residual speech sound disorder: a pilot study

PURPOSE

Children with speech errors who have reduced motor skill may be more likely to develop residual errors associated with lifelong challenges. Drawing on models of speech production that highlight the role of somatosensory acuity in updating motor plans, this pilot study explored the relationship between motor skill and speech accuracy, and between somatosensory acuity and motor skill in children. Understanding the connections among sensorimotor measures and speech outcomes may offer insight into how somatosensation and motor skill cooperate during speech production, which could inform treatment decisions for this population.

METHOD

Twenty-five children (ages 9-14) produced syllables in an /ɹ/ stimulability task before and after an ultrasound biofeedback treatment program targeting rhotics. We first tested whether motor skill (as measured by two ultrasound-based metrics of tongue shape complexity) predicted acoustically measured accuracy (the normalized difference between the second and third formant frequencies). We then tested whether somatosensory acuity (as measured by an oral stereognosis task) predicted motor skill, while controlling for auditory acuity.

RESULTS

One measure of tongue shape complexity was a significant predictor of accuracy, such that higher tongue shape complexity was associated with lower accuracy at pre-treatment but higher accuracy at post-treatment. Based on the same measure, children with better somatosensory acuity produced /ɹ/ tongue shapes that were more complex, but this relationship was only present at post-treatment.

CONCLUSION

The predicted relationships among somatosensory acuity, motor skill, and acoustically measured /ɹ/ production accuracy were observed after treatment, but unexpectedly did not hold before treatment. The surprising finding that greater tongue shape complexity was associated with lower accuracy at pre-treatment highlights the importance of evaluating tongue shape patterns (e.g., using ultrasound) prior to treatment, and has the potential to suggest that children with high tongue shape complexity at pre-treatment may be good candidates for ultrasound-based treatment.

Using the Experience Sampling Method to Examine the Details of Dosage in School-Based Speech Sound Therapy

PURPOSE

The purpose of this project was to collect practice-based evidence regarding dosage in speech sound therapy sessions in school-based settings. Dosage is the number of trials within a therapy session for any one particular child. School-based speech-language pathologists (SLPs) face a variety of obstacles to service delivery, often making the implementation of evidence-based practices difficult. To that end, we were interested in exploring how therapy parameters, such as group size and session frequency were associated with dosage.

METHOD

Using the experience sampling method, we queried school-based SLPs (n = 90) across the United States. SLPs participated via a phone application, which randomly alerted them to participate 3 times per day for 5 days. SLPs also completed a demographic questionnaire that included information regarding caseload size and job satisfaction.

RESULTS

We report results from 670 therapy sessions. Results revealed that the therapy parameter of group size was negatively related to dosage. The SLP parameter of caseload size was positively related to dosage, but this was a small association. The child parameter of comorbidity was negatively related to dosage.

CONCLUSIONS

Our results support that as group size increases, children receive smaller doses of speech sound practice. Similarly, children who have a reported comorbidity received smaller doses compared to children who have an isolated speech sound disorder. We discuss implications for school-based practitioners and researchers.

Differential Diagnosis of Childhood Apraxia of Speech Compared to Other Speech Sound Disorders: A Systematic Review

Purpose The aim of this study was to determine the discriminative features that might contribute to differentiation of childhood apraxia of speech (CAS) from other speech sound disorders (SSDs). Method A comprehensive literature search was conducted for articles or doctoral dissertations that included ≥ 1 child with CAS and ≥ 1 child with SSD. Of 2,071 publications screened, 53 met the criteria. Articles were assessed for (a) study design and risk of bias; (b) participant characteristics and confidence in diagnosis; and (c) discriminative perceptual, acoustic, or kinematic measures. A criterion was used to identify promising studies: American Academy of Neurology study design (Class III+), replicable participant descriptions and adequate confidence in diagnosis (≥ 3), and ≥ 1 discriminative and reliable measure. Results Over 75% of studies were retrospective, case-control designs and/or assessed English-speaking children. Many studies did not fully describe study design and quality. No studies met the Class I (highest) quality rating according to American Academy of Neurology guidelines. CAS was mostly compared to speech delay/phonological disorder. Only six studies had diagnostic confidence ratings of 1 (best). Twenty-six studies reported discriminative perceptual measures, 14 reported discriminative acoustic markers, and four reported discriminative kinematic markers. Measures were diverse, and only two studies directly replicated previous findings. Overall, seven studies met the quality criteria, and another eight nearly met the study criteria to warrant further investigation. Conclusions There are no studies of the highest diagnostic quality. There are 15 studies that can contribute to further diagnostic efforts discriminating CAS from other SSDs. Future research should utilize careful diagnostic design, support replication, and adhere to standard reporting guidelines. Supplemental Material https://doi.org/10.23641/asha.13158149.

PROMPT intervention for children with severe speech motor delay: a randomized control trial

BACKGROUND

Currently, there is limited information on the intervention efficacy for children with speech motor delay (SMD). This randomized control trial (RCT) study examined the effectiveness of Prompts for Restructuring Oral Muscular Phonetic Targets (PROMPT) intervention to improve the outcomes in children with SMD. We hypothesized that children with SMD receiving PROMPT intervention would improve more in the measured outcomes than those waitlisted and receiving home training.

METHODS

Using a two-arm, parallel group, RCT, 49 children with SMD were allocated to either an intervention group (N = 24) that received 45 min of PROMPT intervention two times a week for 10 weeks or were waitlisted for the same duration and received only home training instructions (N = 25). Outcome measures for speech motor control, articulation, speech intelligibility (word and sentence levels), and functional communication were assessed at baseline and at a 10-week follow-up.

RESULTS

PROMPT intervention was associated with notable improvements in speech motor control, speech articulation, and word-level speech intelligibility. Intervention allocation yielded weak improvements in sentence-level speech intelligibility and functional communication.

CONCLUSIONS

PROMPT intervention is a clinically effective intervention approach for children with SMD.

IMPACT

Currently, there is limited information on the intervention efficacy for children with SMD. We report on the findings of a phase III intervention efficacy study on children with SMD using an RCT design. PROMPT intervention is a clinically effective intervention approach for children with SMD. Results of the study will be fundamental to the delivery of effective services for this population. These findings may facilitate the development of an evidence-based care pathway for children with severe speech sound disorders.

The Speech "Bamana": Using the Syllable Repetition Task to Identify Underlying Phonological Deficits in Children With Speech and Language Impairments

Purpose This study compared performance on the Syllable Repetition Task (SRT) by preschoolers with diverse speech and language abilities to identify underlying impairments in speech processes. Method Three groups of 13 children ages 4 and 5 years with (a) typically developing (TD) speech and language, (b) speech sound disorder (SSD), and (c) comorbid developmental language disorder and speech sound disorder (DLD + SSD) completed the SRT. We calculated competence, memory, encoding, and transcoding scores, as well as word-initial stress pattern and vowel accuracy. Results A 3 × 3 (Group × Syllable length) factorial multivariate analysis of covariance revealed group differences for all measures and syllable length differences for memory, transcoding, and competence. There were no interactions between group and syllable length. TD children obtained the highest scores on each measure, though children with DLD + SSD performed similarly to TD children on encoding when vocabulary was included as a covariate. Children with SSD only outperformed children with DLD + SSD on competence and transcoding, and these two groups performed similarly on memory. A separate exploratory analysis using a 3 × 3 multivariate analysis of covariance revealed that children with DLD + SSD were more likely than children in the other groups to produce weak word-initial stress and vowel errors during syllable repetition. Conclusion Children with SSD and DLD + SSD exhibit underlying phonological deficits on the SRT compared to TD children. Results support the claim that memory and encoding are deficits in SSD. In addition, transcoding deficits were identified among children with no known oromotor impairment. Therefore, more research is required to identify the relationship between SRT performance and explicit measures of phonological processing.

Speech Sound Disorders in Children: An Articulatory Phonology Perspective

Speech Sound Disorders (SSDs) is a generic term used to describe a range of difficulties producing speech sounds in children (McLeod and Baker, 2017). The foundations of clinical assessment, classification and intervention for children with SSD have been heavily influenced by psycholinguistic theory and procedures, which largely posit a firm boundary between phonological processes and phonetics/articulation (Shriberg, 2010). Thus, in many current SSD classification systems the complex relationships between the etiology (distal), processing deficits (proximal) and the behavioral levels (speech symptoms) is under-specified (Terband et al., 2019a). It is critical to understand the complex interactions between these levels as they have implications for differential diagnosis and treatment planning (Terband et al., 2019a). There have been some theoretical attempts made towards understanding these interactions (e.g., McAllister Byun and Tessier, 2016) and characterizing speech patterns in children either solely as the product of speech motor performance limitations or purely as a consequence of phonological/grammatical competence has been challenged (Inkelas and Rose, 2007; McAllister Byun, 2012). In the present paper, we intend to reconcile the phonetic-phonology dichotomy and discuss the interconnectedness between these levels and the nature of SSDs using an alternative perspective based on the notion of an articulatory "gesture" within the broader concepts of the Articulatory Phonology model (AP; Browman and Goldstein, 1992). The articulatory "gesture" serves as a unit of phonological contrast and characterization of the resulting articulatory movements (Browman and Goldstein, 1992; van Lieshout and Goldstein, 2008). We present evidence supporting the notion of articulatory gestures at the level of speech production and as reflected in control processes in the brain and discuss how an articulatory "gesture"-based approach can account for articulatory behaviors in typical and disordered speech production (van Lieshout, 2004; Pouplier and van Lieshout, 2016). Specifically, we discuss how the AP model can provide an explanatory framework for understanding SSDs in children. Although other theories may be able to provide alternate explanations for some of the issues we will discuss, the AP framework in our view generates a unique scope that covers linguistic (phonology) and motor processes in a unified manner.

Re-Evaluating Evidence for Best Practice in Paediatric Speech-Language Pathology

BACKGROUND

Systematic reviews of treatment trials for children with speech and language difficulties often exemplify the limited clinical usefulness of the evidence base, reflecting recent literature in evidence-based medicine. Other studies report that clinicians often fail to seek information about best practice, across the health professions. Consequently, clinical researchers, including those in speech-language pathology, have sought alternative methodologies for determining best practice.

SUMMARY

Some approaches focus on "pragmatic trials," usually as part of existing health services. Others place case management of individuals at the centre of intervention presenting studies of one or more cases, including N-of-1 randomized controlled trials and cross-over group designs. Clinical case studies can provide important theoretical data contributing to our understanding of the development of typical and atypical communication. Precision medicine (also known as personalized medicine) is an emerging approach to building the clinical evidence base that acknowledges the importance of individual genetic and environmental differences between people. With increasing knowledge of aetiological heterogeneity, even within children presenting with the same diagnosis (e.g., childhood apraxia of speech), data reinforce the edict that children are not all born equal. Key Message: This review argues that to understand response to treatment, it is critical to examine child-related factors as well as the variables of the intervention itself.

Differential Long-Term Outcomes for Individuals With Histories of Preschool Speech Sound Disorders

Purpose The goal of this study was to determine whether adolescent outcomes for individuals with histories of early speech sound disorders (SSD) could be differentiated by speech and language skills at earlier ages (preschool, 4-6 years, and school age, 7-10 years). Method The study used a retrospective longitudinal design. Participants with and without histories of early SSD were classified in adolescence as having no SSD, resolved SSD, low multisyllabic word (MSW; difficulty with MSW repetition but no errors in conversational speech), or persistent speech disorders (errors in both conversational speech and MSW repetition). Analysis of variance was employed to determine whether early speech, language, and literacy skills distinguished these adolescent outcome groups. Results Preschool and school-age skills differed for adolescents whose SSD had resolved from those who had persistent speech errors. Adolescents with errors solely in production of MSWs (Low MSW) did not differ in early speech and language skills from adolescents who had difficulty with both MSWs and persistent errors in conversation. Conclusions Speech and language assessments earlier in childhood can help establish risks for persistent SSD and other language and literacy difficulties in adolescence. Early identification of these clinically relevant subgroups of SSD may allow for early targeted interventions. Supplemental Material https://doi.org/10.23641/asha.9932279.

Investigating intervention dose frequency for children with speech sound disorders and motor speech involvement

BACKGROUND

Treatment outcome data for children with severe speech sound disorders with motor speech involvement (SSD-MSI) are derived from Phase I clinical research studies. These studies have demonstrated positive improvements in speech production. Currently there is no research examining the optimal treatment dose frequency for this population. The results of this study, which is the first of its kind, will inform the delivery of effective services for this population.

AIMS

To investigate optimal treatment dose frequency for the Motor Speech Treatment Protocol (MSTP) for children with SSD-MSI.

METHODS & PROCEDURES

A total of 48 children (aged 43-47 months) with SSD-MSI participated in the study. Participants received 45-min MSTP intervention sessions either once per week (lower dose frequency) or twice per week (higher dose frequency) for a 10-week period. Blinded outcome assessments were carried out at pre- and post-intervention.

OUTCOMES & RESULTS

Treatment-related change was assessed at body structures, functions and activities participation level as per the World Health Organization's International Classification of Functioning framework: Children and Youth Version (ICF-CY) framework WHO (2007). These measures are related to articulation, functional communication and speech intelligibility. One-way analysis of variance (ANOVA) revealed that for all variables the baseline scores were not statistically different (p > 0.05) between the two dose-frequency groups. Overall, there was a significant main effect of Time (pre-post) across all variables (p < 0.01). However, repeated-measures ANOVA did not result in any statistical interactions (Time × Dose frequency) for any of the variables tested (p > 0.05). Only marginal clinical advantages (< 4% change in intelligibility) were noted with the 10 extra sessions.

CONCLUSIONS & IMPLICATIONS

Overall, the MSTP intervention approach in conjunction with home practice led to significant positive changes for all measures in children with SSD-MSI. No statistical differences between high- and low-dose-frequency groups were observed for any of the variables. Clinical effects were examined using effect sizes, as well as changes in articulation, speech intelligibility and functional communication; these differed marginally between the two dose frequencies. This suggests limited benefits of 10 additional sessions per block. Thus, it is recommended that caregivers, speech-language therapists and policy-makers perform a cost-benefit analysis before determining the dose frequency, when considering additional sessions per block.

Validation of Dodd's Model for Differential Diagnosis of childhood speech sound disorders: a longitudinal community cohort study

AIM

Dodd's Model for Differential Diagnosis is one of the available clinical diagnostic classification systems of childhood speech sound disorders. Yet we do not understand the validity of this system beyond clinical samples, precluding its application in epidemiological or population-based research. This study aimed to determine the prevalence of subgroups of speech sound disorders in a community sample, relative to past clinical samples, in children speaking standard Australian English.

METHOD

We examined speech development in a community-ascertained sample of children at 4 years (n=1607). Inclusion for speech sound disorder was a score of less than or equal to 1 standard deviation on a standardized speech test, and/or research assistant concern, and/or three or more speech errors on sounds typically acquired by 4 years. Dodd's model was then applied to 126 children.

RESULTS

Data revealed proportions of children across Dodd's diagnostic subgroups as follows: suspected atypical speech motor control (10%); inconsistent phonological disorder (15%); consistent atypical phonological disorder (20%); phonological delay (55%); and articulation disorder alone (0%). The findings are in line with known prevalence of these subgroups in clinical populations.

INTERPRETATION

Our findings provide additional support for speech-language pathologists to use this system in clinical practice for differential diagnosis and targeted intervention of speech sound disorders in children.

WHAT THIS PAPER ADDS

Dodd's Model for Differential Diagnosis is the first classification system of speech sound disorders to be applicable to both clinical and community cohorts.

Social-Cognitive and Speech Sound Production Abilities of Minimally Verbal Children With Autism Spectrum Disorders

Purpose To date, there has been a dearth of systematic research that examines both social-cognitive (SC) and speech sound production (SSP) abilities simultaneously in minimally verbal (MV) children with autism spectrum disorders (ASDs). Such an analysis would allow a unified and comprehensive view of the children's communication abilities. The purpose of this study was to develop detailed descriptive profiles of MV children with ASD and uncover patterns in their SC and SSP abilities that may pertain to spoken language. Method This study was a descriptive, multiple clinical case study that examined 5 MV children with ASD, 4 boys and 1 girl, aged 3-6 years. The case studies consisted of demographic information, parent report, and formal and informal assessment of the children. Four SC abilities and 3 SSP abilities were assessed. Results The 5 children's SC score, SSP score, and number of spoken words were converted to z scores. This analysis revealed 2 different patterns of development: 3 of the children had lower SC than SSP abilities, and 2 of the children had the reverse pattern. Conclusions The 5 children were low in both SC and SSP abilities. Although both domains were low, the measure that coincided most with spoken vocabulary among the 5 children was their SSP abilities. Specifically, the children had difficulty in demonstrating emerging control of the onset of voicing for specific speech sounds and verbal imitation of single speech sounds and syllables. Clinical implications of simultaneously assessing and treating SC and SSP abilities in MV children are discussed.

Estimates of the prevalence of speech and motor speech disorders in persons with complex neurodevelopmental disorders

Estimates of the prevalence of speech and motor speech disorders in persons with complex neurodevelopmental disorders (CND) can inform research in the biobehavioural origins and treatment of CND. The goal of this research was to use measures and analytics in a diagnostic classification system to estimate the prevalence of speech and motor speech disorders in convenience samples of speakers with one of eight types of CND. Audio-recorded conversational speech samples from 346 participants with one of eight types of CND were obtained from a database of participants recruited for genetic and behavioural studies of speech sound disorders (i.e., excluding dysfluency) during the past three decades. Data reduction methods for the speech samples included narrow phonetic transcription, prosody-voice coding, and acoustic analyses. Standardized measures were used to cross-classify participants' speech and motor speech status. Compared to the 17.8% prevalence of four types of motor speech disorders reported in a study of 415 participants with idiopathic Speech Delay (SD), 47.7% of the present participants with CND met criteria for one of four motor speech disorders, including Speech Motor Delay (25.1%), Childhood Dysarthria (13.3%), Childhood Apraxia of Speech (4.3%), and concurrent Childhood Dysarthria and Childhood Apraxia of Speech (4.9%). Findings are interpreted to indicate a substantial prevalence of speech disorders, and notably, a substantial prevalence of motor speech disorders in persons with some types of CND. We suggest that diagnostic classification information from standardized motor speech assessment protocols can contribute to research in the pathobiologies of CND. Abbreviations: 16p: 16p11.2 deletion and duplication syndrome; 22q: 22q11.2 deletion syndrome; ASD: Autism Spectrum Disorder; CAS: Childhood Apraxia of Speech; CD: Childhood Dysarthria; CND: Complex Neurodevelopmental Disorder; DS: Down syndrome; FXS: Fragile X syndrome; GAL: Galactosemia; IID: Idiopathic Intellectual Disability; MSD: Motor Speech Disorder; No MSD: No Motor Speech Disorder; NSA: Normal(ized) Speech Acquisition; PEPPER: Programs to Examine Phonetic and Phonologic Evaluation Records; PSD: Persistent Speech Delay; PSE: Persistent Speech Errors; SD: Speech Delay; SDCS: Speech Disorders Classification System; SDCSS: Speech Disorders Classification System Summary; SE: Speech Errors; SMD: Speech Motor Delay; SSD: Speech Sound Disorders; TBI: Traumatic Brain Injury.

Estimates of the prevalence of motor speech disorders in children with idiopathic speech delay

The goal of this research was to obtain initial estimates of the prevalence of each of four types of motor speech disorders in children with idiopathic Speech Delay (SD) and to use findings to estimate the population-based prevalence of each disorder. Analyses were completed on audio-recorded conversational speech samples from 415 children recruited for research in idiopathic SD in six USA cities during the past three decades. The speech and motor speech status of each participant was cross-classified using standardized measures in the finalized version of the Speech Disorders Classification System described in the Supplement. Population-based prevalence estimates for the four motor speech disorders were calculated from epidemiological studies of SD conducted in Australia, England, and the USA. A total of 82.2% of the 415 participants with SD met criteria for No Motor Speech Disorder at assessment, 12% met criteria for Speech Motor Delay, 3.4% met criteria for Childhood Dysarthria, 2.4% met criteria for Childhood Apraxia of Speech, and 0% met criteria for concurrent Childhood Dysarthria and Childhood Apraxia of Speech. The estimated population-based prevalence of each of the first three motor speech disorders at 4 to 8 years of age were Speech Motor Delay: 4 children per 1,000; Childhood Dysarthria: 1 child per 1,000; and Childhood Apraxia of Speech: 1 child per 1,000. The latter finding cross-validates a prior prevalence estimate for Childhood Apraxia of Speech of 1-2 children per 1,000. Findings are interpreted to indicate a substantial prevalence of motor speech disorders in children with idiopathic SD. Abbreviations: CAS, childhood apraxia of speech; CD, childhood dysarthria; CND, complex neurodevelopmental disorders; DI, dysarthria index; DSI, dysarthria subtype indices; MSD, motor speech disorder; No MSD, no motor speech disorder; NSA, normal(ized) speech acquisition; PEPPER, programs to examine phonetic and phonologic evaluation records; PM, pause marker; PMI, pause marker index; PSD, persistent speech delay; PSE, persistent speech errors; SD, speech delay; SDCS, speech disorders classification system; SDCSS, speech disorders classification system summary; SE, speech errors; SMD, speech motor delay.

Data-Driven Classification of Dysarthria Profiles in Children With Cerebral Palsy

Purpose

The objectives of this study were to examine different speech profiles among children with dysarthria secondary to cerebral palsy (CP) and to characterize the effect of different speech profiles on intelligibility.

Method

Twenty 5-year-old children with dysarthria secondary to CP and 20 typically developing children were included in this study. Six acoustic and perceptual speech measures were selected to quantify a range of segmental and suprasegmental speech characteristics and were measured from children's sentence productions. Hierarchical cluster analysis was used to identify naturally occurring subgroups of children who had similar profiles of speech features.

Results

Results revealed 4 naturally occurring speech clusters among children: 1 cluster of children with typical development and 3 clusters of children with dysarthria secondary to CP. Two of the 3 dysarthria clusters had statistically equivalent intelligibility levels but significantly differed in articulation rate and degree of hypernasality.

Conclusion

This study provides initial evidence that different speech profiles exist among 5-year-old children with dysarthria secondary to CP, even among children with similar intelligibility levels, suggesting the potential for developing a pediatric dysarthria classification system that could be used to stratify children with dysarthria into meaningful subgroups for studying speech motor development and efficacy of interventions.

Orofacial Function, Articulation Proficiency, and Intelligibility in 5-Year-Old Children Born With Cleft Lip and Palate

OBJECTIVE

To explore and describe orofacial function in 5-year-old children born with clefts affecting the palate and to investigate potential relationship with articulation proficiency and intelligibility.

DESIGN

A prospective cohort study of 88 consecutive patients born with cleft lip and palate (CLP) between July 2009 and June 2011.

PARTICIPANTS

Excluding internationally adopted children and children with no speech production resulted in 52 children with different cleft types and additional malformations, examined at age 5. Data on orofacial function were available for 43 children.

OUTCOME MEASURES

Screening of orofacial function resulted in a profile and a total score, narrow phonetic transcription of test consonants produced a percentage of consonants correct (PCC) score, and ratings of intelligibility by speech and language pathologists (SLPs) and by parents gave 2 estimates. Inter- and intra-transcriber agreement was calculated.

RESULTS

Orofacial dysfunction was found in 37% of children, with results not significantly different between cleft types but significantly more frequent than in children born without CLP. Age-appropriate articulation proficiency was found in 39%, 49% presented below -2 standard deviations. Just above 50% had good intelligibility and were always understood by different communication partners according to both SLP and parent ratings. No significant correlation was found between orofacial dysfunction and PCC or intelligibility.

CONCLUSIONS

Orofacial dysfunction was not found to be an explanatory factor for speech outcome in children born with CLP.

Phonological encoding in speech-sound disorder: evidence from a cross-modal priming experiment

BACKGROUND

Psycholinguistic models of language production provide a framework for determining the locus of language breakdown that leads to speech-sound disorder (SSD) in children.

AIMS

To examine whether children with SSD differ from their age-matched peers with typical speech and language development (TD) in the ability phonologically to encode lexical items that have been accessed from memory.

METHODS & PROCEDURES

Thirty-six children (18 with TD, 18 with SSD) viewed pictures while listening to interfering words (IW) or a non-linguistic auditory stimulus presented over headphones either 150 ms before, concurrent with or 150 ms after picture presentation. The phonological similarity of the IW and the pictures' names varied. Picture-naming latency, accuracy and duration were tallied.

OUTCOMES & RESULTS

All children named pictures more quickly in the presence of an IW identical to the picture's name than in the other conditions. At the +150 ms stimulus onset asynchrony, pictures were named more quickly when the IW shared phonemes with the picture's name than when they were phonologically unrelated to the picture's name. The size of this effect was similar for children with SSD and children with TD. Variation in the magnitude of inhibition and facilitation on cross-modal priming tasks across children was more strongly affected by the size of the expressive and receptive lexicons than by speech-production accuracy.

CONCLUSIONS & IMPLICATIONS

Results suggest that SSD is not associated with reduced phonological encoding ability, at least as it is reflected by cross-modal naming tasks.

A Diagnostic Marker to Discriminate Childhood Apraxia of Speech From Speech Delay: I. Development and Description of the Pause Marker

Purpose

The goal of this article (PM I) is to describe the rationale for and development of the Pause Marker (PM), a single-sign diagnostic marker proposed to discriminate early or persistent childhood apraxia of speech from speech delay.

Method

The authors describe and prioritize 7 criteria with which to evaluate the research and clinical utility of a diagnostic marker for childhood apraxia of speech, including evaluation of the present proposal. An overview is given of the Speech Disorders Classification System, including extensions completed in the same approximately 3-year period in which the PM was developed.

Results

The finalized Speech Disorders Classification System includes a nosology and cross-classification procedures for childhood and persistent speech disorders and motor speech disorders (Shriberg, Strand, & Mabie, 2017). A PM is developed that provides procedural and scoring information, and citations to papers and technical reports that include audio exemplars of the PM and reference data used to standardize PM scores are provided.

Conclusions

The PM described here is an acoustic-aided perceptual sign that quantifies one aspect of speech precision in the linguistic domain of phrasing. This diagnostic marker can be used to discriminate early or persistent childhood apraxia of speech from speech delay.

Polysyllable productions in preschool children with speech sound disorders: Error categories and the Framework of Polysyllable Maturity

PURPOSE

Children with speech sound disorders (SSD) find polysyllables difficult; however, routine sampling and measurement of speech accuracy are insufficient to describe polysyllable accuracy and maturity. This study had two aims: (1) compare two speech production tasks and (2) describe polysyllable errors within the Framework of Polysyllable Maturity.

METHOD

Ninety-three preschool children with SSD from the Sound Start Study (4;0-5;5 years) completed the Polysyllable Preschool Test (POP) and the Diagnostic Evaluation of Articulation and Phonology (DEAP-Phonology).

RESULT

Vowel accuracy was significantly different between the POP and the DEAP-Phonology. Polysyllables were analysed using the seven Word-level Analysis of Polysyllables (WAP) error categories: (1) substitution of consonants or vowels (97.8% of children demonstrated common use), (2) deletion of syllables, consonants or vowels (65.6%), (3) distortion of consonants or vowels (0.0%), (4) addition of consonants or vowels (0.0%), (5) alteration of phonotactics (77.4%), (6) alteration of timing (63.4%) and (7) assimilation or alteration of sequence (0.0%). The Framework of Polysyllable Maturity described five levels of maturity based on children's errors.

CONCLUSIONS

Polysyllable productions of preschool children with SSD can be analysed and categorised using the WAP and interpreted using the Framework of Polysyllable Maturity.

Genetic Candidate Variants in Two Multigenerational Families with Childhood Apraxia of Speech

Childhood apraxia of speech (CAS) is a severe and socially debilitating form of speech sound disorder with suspected genetic involvement, but the genetic etiology is not yet well understood. Very few known or putative causal genes have been identified to date, e.g., FOXP2 and BCL11A. Building a knowledge base of the genetic etiology of CAS will make it possible to identify infants at genetic risk and motivate the development of effective very early intervention programs. We investigated the genetic etiology of CAS in two large multigenerational families with familial CAS. Complementary genomic methods included Markov chain Monte Carlo linkage analysis, copy-number analysis, identity-by-descent sharing, and exome sequencing with variant filtering. No overlaps in regions with positive evidence of linkage between the two families were found. In one family, linkage analysis detected two chromosomal regions of interest, 5p15.1-p14.1, and 17p13.1-q11.1, inherited separately from the two founders. Single-point linkage analysis of selected variants identified CDH18 as a primary gene of interest and additionally, MYO10, NIPBL, GLP2R, NCOR1, FLCN, SMCR8, NEK8, and ANKRD12, possibly with additive effects. Linkage analysis in the second family detected five regions with LOD scores approaching the highest values possible in the family. A gene of interest was C4orf21 (ZGRF1) on 4q25-q28.2. Evidence for previously described causal copy-number variations and validated or suspected genes was not found. Results are consistent with a heterogeneous CAS etiology, as is expected in many neurogenic disorders. Future studies will investigate genome variants in these and other families with CAS.