Vocal Characteristics of Infants at Risk for Speech Motor Involvement: A Scoping Review.

PURPOSE: The purpose of this scoping review was to (a) summarize methodological characteristics of studies examining vocal characteristics of infants at high risk for neurological speech motor involvement and (b) report the state of the high-quality evidence on vocal characteristic trends of infants diagnosed or at high risk for cerebral palsy (CP). METHOD: The PRISMA (Preferred Reporting Items of Systematic Reviews and Meta-Analyses) extension for scoping reviews was followed for reporting our review. Studies measured prelinguistic vocal characteristics of infants under 24 months with birth risk or genetic conditions known to commonly present with speech motor involvement. Fifty-five studies met criteria for Part 1. Eleven studies met criteria for synthesis in Part 2. RESULTS: A smaller percentage of studies examined infants with or at risk for CP compared to studies examining genetic conditions such as Down syndrome. The median year of publication was 1999, with a median sample size of nine participants. Most studies were conducted in laboratory settings and used human coding of vocalizations produced during caregiver-child interactions. Substantial methodological differences were noted across all studies. A small number of high-quality studies of infants with or at risk for CP revealed high rates of marginal babbling, low rates of canonical babbling, and limited consonant diversity under 24 months. Mixed findings were noted across studies of general birth risk factors. CONCLUSIONS: There is limited evidence available to support the early detection of speech motor involvement. Large methodological differences currently impact the ability to synthesize findings across studies. There is a critical need to conduct longitudinal research with larger sample sizes and advanced, modern technologies to detect vocal precursors of speech impairment to support the accurate diagnosis and prognosis of speech development in infants with CP and other clinical populations.

Perceptual Learning of Dysarthria in Adolescence.

PURPOSE: As evidenced by perceptual learning studies involving adult listeners and speakers with dysarthria, adaptation to dysarthric speech is driven by signal predictability (speaker property) and a flexible speech perception system (listener property). Here, we extend adaptation investigations to adolescent populations and examine whether adult and adolescent listeners can learn to better understand an adolescent speaker with dysarthria. METHOD: Classified by developmental stage, adult (n = 42) and adolescent (n = 40) listeners completed a three-phase perceptual learning protocol (pretest, familiarization, and posttest). During pretest and posttest, all listeners transcribed speech produced by a 13-year-old adolescent with spastic dysarthria associated with cerebral palsy. During familiarization, half of the adult and adolescent listeners engaged in structured familiarization (audio and lexical feedback) with the speech of the adolescent speaker with dysarthria; and the other half, with the speech of a neurotypical adolescent speaker (control). RESULTS: Intelligibility scores increased from pretest to posttest for all listeners. However, listeners who received dysarthria familiarization achieved greater intelligibility improvements than those who received control familiarization. Furthermore, there was a significant effect of developmental stage, where the adults achieved greater intelligibility improvements relative to the adolescents. CONCLUSIONS: This study provides the first tranche of evidence that adolescent dysarthric speech is learnable-a finding that holds even for adolescent listeners whose speech perception systems are not yet fully developed. Given the formative role that social interactions play during adolescence, these findings of improved intelligibility afford important clinical implications.

Intelligibility in Context Scale: Growth Curves for Typically Developing English-Speaking Children Between Ages 2;6 and 9;11.

PURPOSE: The aim of this study was to quantify the clinical utility of the Intelligibility in Context Scale (ICS) English version by characterizing the growth patterns of the ICS composite scores and seven ICS individual item scores of typically developing American English-speaking children. METHOD: Parents of 545 typically developing children aged 2;6-9;11 (years;months) completed the ICS. Using a proportional odds model, we regressed ICS composite scores on age and computed for model-estimated mean and lower quantile ICS composite scores. Logistic regression and proportional odds modeling were utilized to quantify the relationship of individual ICS items and age. RESULTS: ICS composite scores of typically developing children changed with age, but change was small and incremental, with scores compressed between 3 and 5 across the range of ages. An average child (i.e., on the 50th percentile) is expected to have an ICS composite score of 4 beginning at 3;0 and an ICS composite score of 5 by 6;6. On average, parents gave different intelligibility ratings based on communicative partners, and the rating differences between communicative partners decreased with age. CONCLUSIONS: Given that ICS scores increase with age, the expected score for average children also increases. A child's age is a main factor for interpreting ICS scores.

Developmental Cut-Points for Atypical Speech Intelligibility in Children With Cerebral Palsy.

PURPOSE: Early identification of speech motor involvement (SMI) in children with cerebral palsy (CP) is difficult because of overlapping features with many aspects of typical speech development. Quantitative measures of speech intelligibility have the potential to differentiate between children with SMI and those with no SMI (NSMI). We examined thresholds for speech intelligibility development in children with CP relative to the low end of age-specific typical developmental expectations. We sought to determine whether there were intelligibility differences between children with CP and NSMI versus typically developing (TD) age-mates across the range of development and whether there were differences between children with CP who have NSMI and those with CP who have SMI across the range of development based on speech intelligibility. METHOD: We used two large existing data sets that included speech samples from children between the ages of 2.5 and 8 years. One data set included 511 longitudinal speech samples from children with CP; the other included 505 cross-sectional speech samples from TD children. We examined receiver operating characteristic curves and sensitivity/specificity results by age for differentiating among groups of children. RESULTS: TD children versus those with CP and NSMI showed differentiation in their speech intelligibility across all ages, but the strength of differentiation was only marginally above chance. Children with CP and NSMI showed clear differentiation in their speech intelligibility from those with CP and SMI beginning at the earliest age point. Children with CP who have intelligibility below 40% at the age of 3 years have a very high probability of having SMI. CONCLUSIONS: Early intelligibility screening should be performed in children diagnosed with CP. Those with intelligibility below 40% at 3 years of age should be referred immediately for speech assessment and treatment.

Marginal and Canonical Babbling in 10 Infants at Risk for Cerebral Palsy.

PURPOSE: This study is a preliminary quantification and characterization of the development of marginal and canonical syllable patterns in 10 infants at risk for cerebral palsy (CP). METHOD: We calculated marginal and canonical babbling ratios from parent-infant laboratory recordings of 10 infants at two time points, approximately 13 and 16 months of age. The frequency and diversity of labial, coronal, and velar types of marginal and canonical syllables were also examined. Differences across three outcome groups were compared: infants later diagnosed with CP (n = 3, CP group), risk of CP due to ongoing gross motor delays (n = 4, risk group), and current typically developing status with resolved gross motor delays (n = 3, TDx group). Performance on the Mullen Scales was included for perspective on cognitive development. RESULTS: Higher marginal syllable ratios were observed in the CP and risk groups than the TDx group. An increasing canonical syllable ratio across the two ages was consistently observed in the TDx group. The TDx group produced a greater frequency and diversity of canonical syllable types than the risk and CP groups, and of marginal syllable types than the CP group. CONCLUSIONS: This study offers preliminary support for the possibility that speech motor impairment in infants with CP have the potential to be observed and quantified early in vocal development prior to the expected onset of first words. Prolonged rates of marginal syllable forms may be suggestive of speech motor impairment; however, additional longitudinal outcome data over a longer time course and a larger sample of infants are needed to provide further support for this possibility.

Lexical Predictors of Intelligibility in Young Children's Speech.

PURPOSE: Speech perception is a probabilistic process, integrating bottom-up and top-down sources of information, and the frequency and phonological neighborhood of a word can predict how well it is perceived. In addition to asking how intelligible speakers are, it is important to ask how intelligible individual words are. We examined whether lexical features of words influenced intelligibility in young children. In particular, we applied the neighborhood activation model, which posits that a word's frequency and the overall frequency of a word's phonological competitors jointly affect the intelligibility of a word. METHOD: We measured the intelligibility of 165 children between 30 and 47 months in age on 38 different single words. We performed an item response analysis using generalized mixed-effects logistic regression, adding word-level characteristics (target frequency, neighborhood competition, motor complexity, and phonotactic probability) as predictors of intelligibility. RESULTS: There was considerable variation among the words and the children, but between-word variability was larger in magnitude than between-child variability. There was a clear positive effect of target word frequency and a negative effect of neighborhood competition. We did not find a clear negative effect of motor complexity, and phonotactic probability did not have any effect on intelligibility. CONCLUSION: Word frequency and neighborhood competition both had an effect on intelligibility in young children's speech, so listener expectations are an important factor in the selection of items for children's intelligibility assessment.

Perceptual measurement of articulatory goodness in young children: Relationships with age, speech sound acquisition, and intelligibility.

Speech language pathologists regularly use perceptual methods in clinical practice to assess children's speech. In this study, we examined relationships between measures of speech intelligibility, clinical articulation test results, age, and perceptual ratings of articulatory goodness for children. We also examined the extent to which established measures of intelligibility and clinical articulation test results predicted articulatory goodness ratings, and whether goodness ratings were influenced by intelligibility. A sample of 164 (30-47 months) typically developing children provided speech samples and completed a standardised articulation test. Single word intelligibility scores and ratings of articulatory goodness were gathered from 328 naïve listeners; scores on a standardised articulation test were obtained from each child. Bivariate Pearson correlation, linear regression, and linear mixed effects modelling were used for analysis. Results showed that articulatory goodness ratings had the highest correlation with intelligibility, followed by age, followed by articulation score. Age and clinical articulation scores were both significant predictors of goodness ratings, but articulation scores made only a small contribution to prediction. Articulatory goodness ratings were substantially lower for unintelligible words compared to intelligible words, but articulatory goodness scores increased with age at the same rate for unintelligible and intelligible words. Perceptual ratings of articulatory goodness are sensitive to developmental changes in speech production (regardless of intelligibility) and yield a different kind of information than clinical articulation scores from standardised measures.

Longitudinal change in speech classification between 4 and 10 years in children with cerebral palsy.

AIM: To examine speech impairment severity classification over time in a longitudinal cohort of children with cerebral palsy (CP). METHOD: A total of 101 children (58 males, 43 females) between the ages of 4 and 10 years with CP participated in this longitudinal study. Speech severity was rated using the Viking Speech Scale (VSS), a four-level classification rating scale, at 4, 6, 8, and 10 years (age 4 years: mean = 52 months [3 SD]; age 6 years: mean = 75 months [2 SD]; age 8 years: mean = 100 months [4 SD]; age 10 years: mean = 125 months [5 SD]). We used Bayesian mixed-effects ordinal logistic regression to model (1) the extent to which speech severity changed over time and (2) patterns of change across age groups and classification rating group levels. RESULTS: VSS ratings decreased (speech severity became less severe) between 4 and 10 years of age. Children who were first classified in VSS levels I, II, or III at age 4 years had a high probability of staying at, or improving to, VSS level I by 10 years. Children who were first classified in VSS level IV at 4 years had a high probability of remaining in VSS level IV at 10 years. INTERPRETATION: Early speech performance is highly predictive of later childhood speech abilities. Children with any level of speech impairment at age 4 years should be receiving speech therapy. Those with more severe speech impairments should be introduced to augmentative and alternative communication as soon as possible. WHAT THIS PAPER ADDS: Children with early Viking Speech Scale (VSS) ratings below level IV have a good prognosis for speech improvement. Children with early VSS level IV ratings are likely to remain at VSS level IV over time. Children did not show worsening of VSS level between the ages of 4 and 10 years.

Cambio longitudinal en la clasificación del habla entre los 4 y 10 años en niños con parálisis cerebral OBJETIVO: Examinar la clasificación de la gravedad del deterioro del habla a lo largo del tiempo en una cohorte longitudinal de niños con parálisis cerebral (PC) entre las edades de 4 y 10 años. MÉTODO: Un total de 101 niños (58 varones, 43 mujeres) con PC participaron en este estudio longitudinal. La gravedad del habla se evaluó utilizando la Viking Speech Scale (VSS), una escala de calificación de clasificación de cuatro niveles, a los 4, 6, 8 y 10 años (edad 4 años: media = 52 meses [3 DE]; edad 6 años: media = 75 meses [2 DE]; edad 8 años: media = 100 meses [4 DE]; edad 10 años: media = 125 meses [5 DE]). Utilizamos la regresión logística ordinal de efectos mixtos bayesianos para modelar (1) la medida en que la severidad del habla cambió con el tiempo y (2) los patrones de cambio entre los grupos de edad y los niveles de clasificación de los grupos. RESULTADOS: Las calificaciones de VSS disminuyeron (la severidad del habla se volvió menos severa) entre los 4 y los 10 años de edad. Los niños que fueron clasificados por primera vez en los niveles I, II o III de VSS a los 4 años tenían una alta probabilidad de permanecer en el nivel I de VSS o mejorar al nivel I de VSS a los 10 años. Los niños que fueron clasificados por primera vez en el nivel IV de VSS a los 4 años tenían una alta probabilidad de permanecer en el nivel IV de VSS a los 10 años. INTERPRETACIÓN: El desempeño temprano del habla es altamente predictivo de las habilidades del habla en la niñez posterior. Los niños con cualquier nivel de discapacidad del habla a la edad de 4 años deben recibir terapia del habla. Aquellos con impedimentos del habla más severos deben ser introducidos a la comunicación aumentativa y alternativa tan pronto como sea posible.

Mudança longitudinal na classificação da fala entre 4 e 10 anos em crianças com paralisia cerebral OBJETIVO: Analisar a classificação da gravidade do comprometimento da fala ao longo do tempo em uma coorte longitudinal de crianças com paralisia cerebral (PC) entre 4 e 10 anos. MÉTODO: Um total de 101 crianças (58 meninos, 43 meninas) com PC participaram deste estudo longitudinal. A gravidade da fala foi avaliada usando a Viking Speech Scale (VSS), uma escala de classificação de quatro níveis, aos 4, 6, 8 e 10 anos (idade 4 anos: média = 52 meses [3 DP]; idade 6 anos: média = 75 meses [2 DP]; idade 8 anos: média = 100 meses [4 DP]; idade 10 anos: média = 125 meses [5 DP]). Usamos a regressão logística ordinal Bayesiana de efeitos mistos para modelar (1) a extensão em que a gravidade da fala mudou ao longo do tempo e (2) padrões de mudança entre as faixas etárias e os níveis de classificação do grupo. RESULTADOS: As classificações de VSS diminuíram (a gravidade da fala tornou-se menos grave) entre 4 e 10 anos de idade. As crianças que foram classificadas pela primeira vez nos níveis VSS I, II ou III aos 4 anos de idade tiveram uma alta probabilidade de permanecer ou melhorar para o nível VSS I em 10 anos. As crianças que foram classificadas pela primeira vez em VSS nível IV aos 4 anos tiveram alta probabilidade de permanecer no VSS nível IV aos 10 anos. INTERPRETAÇÃO: O desempenho precoce da fala é altamente preditivo de habilidades de fala na infância posteriormente. Crianças com qualquer nível de deficiência de fala aos 4 anos de idade devem receber terapia da fala. Aqueles com deficiências de fala mais graves devem ser introduzidos à comunicação aumentativa e alternativa o mais rápido possível.

Functional Communication Abilities in Youth With Cerebral Palsy: Association With Impairment Profiles and School-Based Therapy Goals.

PURPOSE: The aim of this study was to examine the relationship between functional communication skills, underlying speech, language, and cognitive impairments and school-based speech pathology services in students with cerebral palsy (CP). METHOD: Thirty-five participants with CP who had Individualized Education Programs (IEPs) were classified according to the Communication Function Classification System (CFCS). Participants completed laboratory assessments of speech, receptive language, executive functioning, and nonverbal cognition. Each participant's speech and language IEP goals were coded into treatment units and then categorized into seven, mutually exclusive target goal areas. Nonparametric analyses were employed to examine differences among CFCS groups in the number of deficit areas and the number of goal areas from the IEP. Descriptive analyses were used to evaluate the extent to which deficit and goal areas in the IEP co-occurred by CFCS level. RESULTS: Those in more involved CFCS levels demonstrated more severe speech, receptive language, and cognitive impairments. However, there were no significant differences in the number of deficit areas across CFCS groups. Regardless of CFCS level, there were no differences in the number of treatment goals specified in the IEP. Literacy was the only goal area addressed across all CFCS levels. Those in the most involved CFCS levels had augmentative and alternative communication (AAC) goals, but those with more moderate restrictions in functional communication who also had markedly reduced speech intelligibility did not typically have speech or AAC goals. INTERPRETATION: Individuals with CP across CFCS levels demonstrate variability in underlying deficit profiles, suggesting that measures of both functional communication and of underlying deficits are necessary to provide a complete picture of communication needs. Literacy goals were common across all CFCS levels, but AAC goals were limited to the most severely involved individuals, suggesting that continuing education may be necessary to support speech-language pathologists in developing treatments involving the integration of AAC and speech to foster functional communication at school. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.16968073.

Utility of the Intelligibility in Context Scale for Predicting Speech Intelligibility of Children with Cerebral Palsy.

The Intelligibility in Context Scale (ICS) is a widely used, efficient tool for describing a child's speech intelligibility. Few studies have explored the relationship between ICS scores and transcription intelligibility scores, which are the gold standard for clinical measurement. This study examined how well ICS composite scores predicted transcription intelligibility scores among children with cerebral palsy (CP), how well individual questions from the ICS differentially predicted transcription intelligibility scores, and how well the ICS composite scores differentiated between children with and without speech motor impairment. Parents of 48 children with CP, who were approximately 13 years of age, completed the ICS. Ninety-six adult naïve listeners provided orthographic transcriptions of children's speech. Transcription intelligibility scores were regressed on ICS composite scores and individual item scores. Dysarthria status was regressed on ICS composite scores. Results indicated that ICS composite scores were moderately strong predictors of transcription intelligibility scores. One individual ICS item differentially predicted transcription intelligibility scores, and dysarthria severity influenced how well ICS composite scores differentiated between children with and without speech motor impairment. Findings suggest that the ICS has potential clinical utility for children with CP, especially when used with other objective measures of speech intelligibility.

Speech Development Between 30 and 119 Months in Typical Children II: Articulation Rate Growth Curves.

Purpose We aimed to develop normative growth curves for articulation rate during sentence repetition for typically developing children. Our primary goal was the development of quantile/percentile growth curves so that typical variation in articulation rate with age could be estimated. We also estimated when children became adultlike in their articulation rate, and we examined the contributions of age and utterance length to articulation rate. Method This cross-sectional study involved collection of in-person speech samples from 570 typically developing children (297 girls; 273 boys) who passed speech, language, and hearing screening measures. Pauses greater than 150 ms in duration were removed from the samples, and articulation rate was measured in syllables per second (sps). Results Articulation rate reliably increased with age and utterance length. Rate in all key percentiles increased with age. The median rate (50th percentile) increased from 2.7 sps at 36 months to 3.3 sps at 96 months. The 5th percentile increased from 2.3 to 3.1 sps over the same age range. Using 3.2 sps as a benchmark for adultlike speech, we found the 25th, 50th, and 75th percentiles reached adultlike rates at 99, 75, and 53 months, respectively. Conclusions Articulation rate increases from early childhood into middle childhood, and it is generally adultlike by 10 years of age. Variability in articulation rate among typical children was substantial. Implications for prior research and for clinical usage are discussed.

Speech Development Between 30 and 119 Months in Typical Children I: Intelligibility Growth Curves for Single-Word and Multiword Productions.

Purpose We extended our earlier study on normative growth curves for intelligibility development in typical children from 30 to 119 months of age. We also determined quantile-specific age of steepest growth and growth rates. A key goal was to establish age-specific benchmarks for single-word and multiword intelligibility. Method This cross-sectional study involved collection of in-person speech samples from 538 typically developing children (282 girls and 256 boys) who passed speech, language, and hearing screening measures. One thousand seventy-six normal-hearing naïve adult listeners (280 men and 796 women) orthographically transcribed children's speech. Speech intelligibility was measured as the percentage of words transcribed correctly by naive adults, with single-word and multiword intelligibility outcomes modeled separately. Results The age range for 50% single-word intelligibility was 31-47 months (50th-5th percentiles), the age range for 75% single-word intelligibility was 49-87 months, and the age range for 90% intelligibility for single words was 83-120+ months. The same milestones were attained for multiword intelligibility at 34-46, 46-61, and 62-87 months, respectively. The age of steepest growth for the 50th percentile was 30-31 months for both single-word and multiword intelligibility and was later for children in lower percentiles. The maximum growth rate was 1.7 intelligibility percentage points per month for single words and 2.5 intelligibility percentage points per month for multiword intelligibility. Conclusions There was considerable variability in intelligibility development among typical children. For children in median and lower percentiles, intelligibility growth continues through 9 years. Children should be at least 50% intelligible by 48 months. Supplemental Material https://doi.org/10.23641/asha.16583426.

Performance of Forced-Alignment Algorithms on Children's Speech.

Purpose Acoustic measurement of speech sounds requires first segmenting the speech signal into relevant units (words, phones, etc.). Manual segmentation is cumbersome and time consuming. Forced-alignment algorithms automate this process by aligning a transcript and a speech sample. We compared the phoneme-level alignment performance of five available forced-alignment algorithms on a corpus of child speech. Our goal was to document aligner performance for child speech researchers. Method The child speech sample included 42 children between 3 and 6 years of age. The corpus was force-aligned using the Montreal Forced Aligner with and without speaker adaptive training, triphone alignment from the Kaldi speech recognition engine, the Prosodylab-Aligner, and the Penn Phonetics Lab Forced Aligner. The sample was also manually aligned to create gold-standard alignments. We evaluated alignment algorithms in terms of accuracy (whether the interval covers the midpoint of the manual alignment) and difference in phone-onset times between the automatic and manual intervals. Results The Montreal Forced Aligner with speaker adaptive training showed the highest accuracy and smallest timing differences. Vowels were consistently the most accurately aligned class of sounds across all the aligners, and alignment accuracy increased with age for fricative sounds across the aligners too. Conclusion The best-performing aligner fell just short of human-level reliability for forced alignment. Researchers can use forced alignment with child speech for certain classes of sounds (vowels, fricatives for older children), especially as part of a semi-automated workflow where alignments are later inspected for gross errors. Supplemental Material https://doi.org/10.23641/asha.14167058.

Reliability of Perceptual Judgments of Phonetic Accuracy and Hypernasality Among Speech-Language Pathologists for Children With Dysarthria.

Purpose The objectives of this study were to: (a) compare interrater reliability of practicing speech-language pathologists' (SLPs) perceptual judgments of phonetic accuracy and hypernasality between children with dysarthria and those with typical development, and (b) to identify speech factors that influence reliability of these perceptual judgments for children with dysarthria. Method Ten SLPs provided ratings of speech samples from twenty 5-year-old children with dysarthria and twenty 5-year-old children with typical development on two tasks via a web-based platform: a hypernasality judgment task and a phonetic accuracy judgment task. Interrater reliability of SLPs' ratings on both tasks was compared between children with dysarthria and children with typical development. For children with dysarthria, four acoustic speech measures, intelligibility, and a measure of phonetic accuracy (percent stops correct) were examined as predictors of reliability of SLPs' perceptual judgments. Results Reliability of SLPs' phonetic accuracy judgments and hypernasality ratings was significantly lower for children with dysarthria than for children with typical development. Among children with dysarthria, interrater reliability of perceptual judgments ranged from strong to weak. Percent stops correct was the strongest predictor of interrater reliability for both phonetic accuracy judgments and hypernasality ratings. Conclusions Reliability of perceptual phonetic accuracy judgments and hypernasality ratings among practicing SLPs for children with dysarthria is reduced compared to ratings for children with typical development. Findings underscore the need for more reliable methods to assess phonetic accuracy and hypernasality for children with dysarthria.

Speech-Language Profile Groups in School Aged Children with Cerebral Palsy: Nonverbal Cognition, Receptive Language, Speech Intelligibility, and Motor Function.

Purpose: To explore the relationship of intelligibility, receptive language, executive functioning, and motor skills to nonverbal cognitive skills among children with cerebral palsy (CP) in different speech-language profile groups. Method: Twenty-seven children with CP aged 10-12 years old participated in the study. They completed a battery of standard clinical assessments. The relationship of various skillsets with nonverbal cognitive ability was explored using correlational procedures. Additionally, we examined pairwise differences in nonverbal cognitive skills among profile groups. Cohen's Kappa and Chi-square tests were used to study the consistency of receptive language and nonverbal cognitive performance. Results: Children who showed better nonverbal cognitive abilities demonstrated better motor, receptive language, and intelligibility skills. Nonverbal cognition was generally consistent with receptive language. Conclusion: Nonverbal cognitive impairment often co-occurs with language and speech motor impairment among children with CP. Speech-language profile groups are a useful framework for describing both communication and cognitive abilities.

Validity of Parent Ratings of Speech Intelligibility for Children with Cerebral Palsy.

Aim: To examine the relationship between subjective parent ratings of intelligibility and objectively measured intelligibility scores for children with cerebral palsy (CP) with differing levels of speech severity. Method: Fifty children (84-96 months) with CP were classified into groups based on intelligibility scores during a speech elicitation task - high intelligibility (90% or higher), mild-moderate intelligibility reduction (61-89%), and severe intelligibility reduction (60% or lower). Parent ratings of understandability (on a 7-point scale) were compared to intelligibility scores gathered from 100 naïve listeners. Results: For children with mild-moderate and severe intelligibility reduction, there was a large range of variability in parent ratings. For children with high intelligibility, ratings were consistent with intelligibility scores. There was a range of intelligibility scores within each rating, especially in the middle of the scale. Conclusions: For children with mild-moderate intelligibility deficits, parent ratings may best be used in conjunction with objective measurement of intelligibility.

Longitudinal Growth in Intelligibility of Connected Speech From 2 to 8 Years in Children With Cerebral Palsy: A Novel Bayesian Approach.

Aim The aim of the study was to examine longitudinal growth in intelligibility in connected speech from 2 to 8 years of age in children with cerebral palsy. Method Sixty-five children with cerebral palsy participated in the longitudinal study. Children were classified into speech-language profile groups using age-4 data: no speech motor impairment (SMI), SMI with typical language comprehension, and SMI with impaired language comprehension. We fit a Bayesian nonlinear mixed-effects model of intelligibility growth at the child and group levels. We compared groups by age of steepest growth, maximum growth rate, and predicted intelligibility at 8 years of age. Results The no SMI group showed earlier and steeper intelligibility growth and higher average outcomes compared to the SMI groups. The SMI groups had more variable growth trajectories, but the SMI with typical language comprehension group had higher age-8 outcomes and steeper rates of maximum growth than the SMI with impaired language comprehension group. Language comprehension impairment at age of 4 years predicted lower intelligibility outcomes at age of 8 years, compared to typical language at age of 4 years. Interpretation Children with SMI at age of 4 years show highly variable intelligibility growth trajectories, and comorbid language comprehension impairment predicts lower intelligibility outcomes. Supplemental Material https://doi.org/10.23641/asha.12777659.

Measuring Speech Production Development in Children With Cerebral Palsy Between 6 and 8 Years of Age: Relationships Among Measures.

Purpose Accurate measurement of speech intelligibility is essential for children with speech production deficits, but wide variability exists in the measures and protocols used. The current study sought to examine relationships among measures of speech intelligibility and the capacity of different measures to capture change over time. Method Forty-five children with cerebral palsy (CP) with and without speech motor impairment were observed at ages 6, 7, and 8 years. The speech performance of each child was rated using four measures at each time point: standardized articulation test scores, multiword intelligibility scores obtained from naïve listeners, parent ratings of intelligibility, and percent intelligible utterances obtained from language transcripts. We analyzed the correlations of measures within each age and within three different severity groups, and we analyzed how these measures changed year over year in each severity group. Results For children with CP who have mild and moderate speech deficits, different measures of speech production were weakly associated, and for children with CP with severe speech impairment, these measures showed stronger associations. The four measures also differed in their ability to capture change over time. Finally, results from standardized assessments of articulation were not found to inform overall speech intelligibility for children with mild and moderate speech deficits. Conclusions Results suggest that speech production is not fully described by any single clinical measure. In order to adequately describe functional speaking abilities and to capture change over time, multiple levels of measurement are required.

Development of Speech Intelligibility Between 30 and 47 Months in Typically Developing Children: A Cross-Sectional Study of Growth.

Purpose We sought to establish normative growth curves for intelligibility development for the speech of typically developing children as revealed by objectively based orthographic transcription of elicited single-word and multiword utterances by naïve listeners. We also examined sex differences, and we compared differences between single-word and multiword intelligibility growth. Method One hundred sixty-four typically developing children (92 girls, 72 boys) contributed speech samples for this study. Children were between the ages of 30 and 47 months, and analyses examined 1-month age increments between these ages. Two different naïve listeners heard each child and made orthographic transcriptions of child-produced words and sentences (n = 328 listeners). Average intelligibility scores for single-word productions and multiword productions were modeled using linear regression, which estimated normal-model quantile age trajectories for single- and multiword utterances. Results We present growth curves showing steady linear change over time in 1-month increments from 30 to 47 months for 5th, 10th, 25th, 50th, 75th, 90th, and 95th percentiles. Results showed that boys did not differ from girls and that, prior to 35 months of age, single words were more intelligible than multiword productions. Starting at 41 months of age, the reverse was true. Multiword intelligibility grew at a faster rate than single-word intelligibility. Conclusions Children make steady progress in intelligibility development through 47 months, and only a small number of children approach 100% intelligibility by this age. Intelligibility continues to develop past the fourth year of life. There is considerable variability among children with regard to intelligibility development. Supplemental Material https://doi.org/10.23641/asha.12330956.

Communication Modes and Functions in Children With Cerebral Palsy.

Purpose This study seeks to determine how speech-language impairments relate to the frequency and diversity of communication modes and functions produced by children with cerebral palsy (CP) during interactions with their mothers. Method We studied 40 children with CP (M age = 62 months) comprising three groups: those who were unable to speak and had anarthria (n = 15), those with speech motor impairment and language comprehension impairment (SMI-LCI; n = 15), and those with speech motor impairment and typical language comprehension (SMI-LCT; n = 10). Mother-child play interactions were coded for child modes and functions. Generalized linear regression models were used to examine the relationship between profile group and frequencies of communication modes and functions. Results Results indicated groups SMI-LCI and SMI-LCT had significantly higher mean frequencies of vocalizations, vocalizations + gestures, comments, initiations, and requests than the group of those who were unable to speak and had anarthria. All children used vocalizations primarily, though these vocalizations were often not understood. SMI-LCI and SMI-LCT differed on two measures: frequency of gestures and frequency of initiations. The majority of children in this sample did not have access to augmentative and alternative communication devices. Conclusion Results of this study highlight the need for parent-mediated interventions for children with CP that emphasize multimodal communication tailored to impairment profiles. Supplemental Material https://doi.org/10.23641/asha.12354704.