The Fifth Croatia Stuttering Symposium: Part I. Treatments for early stuttering.

PURPOSE: The Fifth Croatia Stuttering Symposium in 2022 continued the Fourth Croatia Stuttering Symposium 2019 theme of the connection between research and clinical practice. At the 2022 Symposium, there were 145 delegates from 21 countries. This paper documents the contents of the first of three Symposium modules. METHODS: The module topic was that three treatments for early childhood stuttering are supported by randomized controlled trial evidence. A clinical situation was considered where a parent of a 3-year-old child asked what results to expect of stuttering treatment. RESULTS: A distinguished scholar presented a 5-minute video interpretation of the research concerning the randomized controlled trial evidence for the three treatments. Three master clinicians then each presented a 2-minute video demonstration of how those research findings might be applied in a clinical situation. Following that, the convenors moderated a discussion between the distinguished scholar, master clinicians, and delegates regarding the research and how it applies to clinical practice.

Decontextualized Utterances Contain More Typical and Stuttering-Like Disfluencies in Preschoolers Who Do and Do Not Stutter.

PURPOSE: Stuttering-like disfluencies (SLDs) and typical disfluencies (TDs) are both more likely to occur as utterance length increases. However, longer and shorter utterances differ by more than the number of morphemes: They may also serve different communicative functions or describe different ideas. Decontextualized language, or language that describes events and concepts outside of the "here and now," is associated with longer utterances. Prior work has shown that language samples taken in decontextualized contexts contain more disfluencies, but averaging across an entire language sample creates a confound between utterance length and decontextualization as contributors to stuttering. We coded individual utterances from naturalistic play samples to test the hypothesis that decontextualized language leads to increased disfluencies above and beyond the effects of utterance length. METHOD: We used archival transcripts of language samples from 15 preschool children who stutter (CWS) and 15 age- and sex-matched children who do not stutter (CWNS). Utterances were coded as either contextualized or decontextualized, and we used mixed-effects logistic regression to investigate the impact of utterance length and decontextualization on SLDs and TDs. RESULTS: CWS were more likely to stutter when producing decontextualized utterances, even when controlling for utterance length. An interaction between decontextualization and utterance length indicated that the effect of decontextualization was greatest for shorter utterances. TDs increased in decontextualized utterances when controlling for utterance length for both CWS and CWNS. The effect of decontextualization on TDs did not differ statistically between the two groups. CONCLUSIONS: The increased working memory demands associated with decontextualized language contribute to increased language planning effort. This leads to increased TD in CWS and CWNS. Under a multifactorial dynamic model of stuttering, the increased language demands may also contribute to increased stuttering in CWS due to instabilities in their speech motor systems.

Stalling for Time: Stall, Revision, and Stuttering-Like Disfluencies Reflect Language Factors in the Speech of Young Children.

PURPOSE: Disfluencies can be classified as stuttering-like disfluencies (SLDs) or typical disfluencies (TDs). Dividing TDs further, stalls (fillers and repetitions) are thought to be prospective, occurring due to planning glitches, and revisions (word and phrase revisions, word fragments) are thought to be retrospective, occurring when a speaker corrects language produced in error. In the first study assessing stalls, revisions, and SLDs in matched groups of children who stutter (CWS) and children who do not stutter (CWNS), we hypothesized that SLDs and stalls would increase with utterance length and grammaticality but not with a child's expressive language level. We expected revisions to be associated with a child having more advanced language but not with utterance length or grammaticality. We hypothesized that SLDs and stalls (thought to be planning-related) would tend to precede grammatical errors. METHOD: We analyzed 15,782 utterances from 32 preschool-age CWS and 32 matched CWNS to assess these predictions. RESULTS: Stalls and revisions increased in ungrammatical and longer utterances and with the child's language level. SLDs increased in ungrammatical and longer utterances, but not with overall language level. SLDs and stalls tended to occur before grammatical errors. CONCLUSIONS: Results suggest that both stalls and revisions are more likely to occur in utterances that are harder to plan (those that are ungrammatical and/or longer) and that, as children's language develops, so do the skills they need to produce both stalls and revisions. We discuss clinical implications of the finding that ungrammatical utterances are more likely to be stuttered.

What Is the Role of Questioning in Young Children's Fluency?

PURPOSE: Most therapy programs for young children who stutter (CWS) involve caregiver counseling and adjustment of caregiver behavior to maximize opportunities for the child to be more fluent. One component sometimes included as a recommended adjustment is a reduction in caregiver question asking, as question asking is hypothesized to increase language formulation demands on the child. However, there is limited research to guide clinician advisement to caregivers that has controlled for numerous potential confounding factors, including utterance length and grammaticality, that may impact potential stressors on children. Our aim was to assess whether there was an empirical basis for such recommendations by comparing disfluency profiles of answers to questions and nonanswer utterances produced by children during spontaneous play with parents and examiners. METHOD: We analyzed fluency and structural properties as well as pragmatic function of 15,782 utterances from language samples produced by 32 CWS and 32 children who do not stutter (CWNS) who were between 28 and 50 months of age. CWS and CWNS were matched on gender and age within 4 months and were matched as closely as possible on maternal education. RESULTS: For utterances produced by CWS, answers to adult questions were significantly less likely to contain stuttering-like disfluencies than other utterance types, and this was still true after controlling for utterance length and grammaticality. In contrast, for utterances produced by CWNS, answers to questions were significantly more likely to be disfluent than other utterance types after controlling for length and grammaticality. CONCLUSION: Given the current findings, some prior research, and the documented potential benefits in language development for adult question asking of children, we do not believe that clinicians need to recommend changes to typical question-asking behavior by caregivers of CWS.

Measurement of Lexical Diversity in Children's Spoken Language: Computational and Conceptual Considerations.

Background: Type-Token Ratio (TTR), given its relatively simple hand computation, is one of the few LSA measures calculated by clinicians in everyday practice. However, it has significant well-documented shortcomings; these include instability as a function of sample size, and absence of clear developmental profiles over early childhood. A variety of alternative measures of lexical diversity have been proposed; some, such as Number of Different Words/100 (NDW) can also be computed by hand. However, others, such as Vocabulary Diversity (VocD) and the Moving Average Type Token Ratio (MATTR) rely on complex resampling algorithms that cannot be conducted by hand. To date, no large-scale study of all four measures has evaluated how well any capture typical developmental trends over early childhood, or whether any reliably distinguish typical from atypical profiles of expressive child language ability. Materials and Methods: We conducted linear and non-linear regression analyses for TTR, NDW, VocD, and MATTR scores for samples taken from 946 corpora from typically developing preschool children (ages 2-6 years), engaged in adult-child toy play, from the Child Language Data Exchange System (CHILDES). These were contrasted with 504 samples from children known to have delayed expressive language skills (total n = 1,454 samples). We also conducted a separate sub-analysis which examined possible contextual effects of sampling environment on lexical diversity. Results: Only VocD showed significantly different mean scores between the typically -developing children and delayed developing children group. Using TTR would actually misdiagnose typical children and miss children with known language impairment. However, computation of VocD as a function of toy interactions was significant and emerges as a further caution in use of lexical diversity as a valid proxy index of children's expressive vocabulary skill. Discussion: This large scale statistical comparison of computer-implemented algorithms for expressive lexical profiles in young children with traditional, hand-calculated measures showed that only VocD met criteria for evidence-based use in LSA. However, VocD was impacted by sample elicitation context, suggesting that non-linguistic factors, such as engagement with elicitation props, contaminate estimates of spoken lexical skill in young children. Implications and suggested directions are discussed.

Dynamic Norming and Open Science.

In a recent issue of JSLHR, Tucci et al. (2022) presented a method for assigning SEM scores to a language sample. However, this method is based on data that are not publicly available and uses a commercial analysis program that is not open source. The TalkBank system and the Child Language Data Exchange System database provides free analysis software based on openly accessible data, thereby adhering to Open Science standards, which represent an important next step for the fields of speech and hearing.

Acoustic-Lexical Characteristics of Child-Directed Speech Between 7 and 24 Months and Their Impact on Toddlers' Phonological Processing.

Speech-language input from adult caregivers is a strong predictor of children's developmental outcomes. But the properties of this child-directed speech are not static over the first months or years of a child's life. This study assesses a large cohort of children and caregivers (n = 84) at 7, 10, 18, and 24 months to document (1) how a battery of phonetic, phonological, and lexical characteristics of child-directed speech changes in the first 2 years of life and (2) how input at these different stages predicts toddlers' phonological processing and vocabulary size at 2 years. Results show that most measures of child-directed speech do change as children age, and certain characteristics, like hyperarticulation, actually peak at 24 months. For language outcomes, children's phonological processing benefited from exposure to longer (in phonemes) words, more diverse word types, and enhanced coarticulation in their input. It is proposed that longer words in the input may stimulate children's phonological working memory development, while heightened coarticulation simultaneously introduces important sublexical cues and exposes them to challenging, naturalistic speech, leading to overall stronger phonological processing outcomes.

Change in maternal speech rate to preverbal infants over the first two years of life.

Aims: Although IDS is typically described as slower than adult-directed speech (ADS), potential impacts of slower speech on language development have not been examined. We explored whether IDS speech rates in 42 mother-infant dyads at four time periods predicted children's language outcomes at two years. Method: We correlated IDS speech rate with child language outcomes at two years, and contrasted outcomes in dyads displaying high/low rate profiles. Outcomes: Slower IDS rate at 7 months significantly correlated with vocabulary knowledge at two years. Slowed IDS may benefit child language learning even before children first speak.

Lexical diversity and lexical skills in children who stutter.

PURPOSE: Numerous "small N" studies of language ability in children who stutter have produced differing conclusions. We combined test and spontaneous language data from a large cohort of children who stutter (CWS) and typically fluent peers, gathered from independent laboratories across the US, to appraise a variety of lexical measures. METHOD: Standardized receptive and expressive vocabulary test data and spontaneous language samples from 99 pairs of CWS (ages 25-100 months), and age-, gender-, and SES-matched children who do not stutter (CWNS) were compared. Language sample transcripts were analyzed with four measures of lexical diversity. Correlations between lexical diversity measures and expressive vocabulary scores were also calculated. RESULTS: On standardized tests of both receptive and expressive vocabulary, there were significant differences between CWS and CWNS. In contrast, on spontaneous language measures of lexical diversity, CWS did not differ in their lexical diversity, across analyses, compared to CWNS. Three of the four lexical diversity analyses, MATTR, VocD, and NDW, were significantly correlated with each other. CONCLUSIONS: We were able to confirm prior findings of relative disadvantage on standardized vocabulary tests for a very large sample of well-matched CWS. However, spontaneous language measures of lexical diversity did not distinguish the groups. This relative weakness in CWS may emerge from task differences: CWS are free to encode their own spontaneous utterances but must comply with explicit lexical prompts in standardized testing situations.

Early Phonological Predictors of Toddler Language Outcomes.

PURPOSE: Several studies have explored relationships between children's early phonological development and later language performance. This literature has included a more recent focus on the potential for early phonological profiles to predict later language outcomes. METHODS: The present study longitudinally examined the nature of phonetic inventories and syllable structure patterns of 48 typically developing children at 7, 11, and 18 months, and related them to expressive language outcomes at 2 years of age. RESULTS: Findings provide evidence that as early as 11 months, phonetic inventory and mean syllable structure level are related to 24-month expressive language outcomes, including mean length of utterance and vocabulary diversity in spontaneous language samples, and parent-reported vocabulary scores. Consonant inventories in particular differed at 11 and 18 months for 2-year-olds with lower versus higher language skills. CONCLUSION: Limited inventories and syllable repertoires may add to risk profiles for later language delays.

Language Growth Predicts Stuttering Persistence Over and Above Family History and Treatment Experience: Response to Marcotte.

Purpose This response addresses comments made by Marcotte (2019) regarding our recent publication, "Preliminary Evidence That Growth in Productive Language Differentiates Childhood Stuttering Persistence and Recovery" ( Leech, Bernstein Ratner, Brown, & Weber, 2017 ). Marcotte calls into question our finding that language growth is a valid predictor of recovery from stuttering because we did not account for treatment and family history. Conclusions In response to her comments, we provide additional empirical analyses couched in a larger discussion of the difficulty of calibrating treatment and family history of stuttering. In short, we show that once treatment history and family history of stuttering are accounted for, the effect of language growth remains a significant predictor of stuttering persistence.

Use of a phoneme monitoring task to examine lexical access in adults who do and do not stutter.

Previous work has postulated that a deficit in lexicalization may be an underlying cause of a stuttering disorder (Prins, Main, & Wampler, 1997; Wingate, 1988). This study investigates the time course of lexicalization of nouns and verbs in adults who stutter. A generalized phoneme monitoring (PM) paradigm was used. Adults who stutter (AWS) and typically-fluent peers both showed an expected effect of word class (verbs yielded slower and less accurate monitoring than nouns), as well as phoneme position (word medial/final phonemes yielded slower and less accurate monitoring than word initial phonemes). However, AWS had considerably more difficulty when targets to be monitored were embedded in the medial position. A negative correlation between speed and accuracy was found in typically fluent adults, but not in AWS. AWS also scored nonsignificantly more poorly on an experimental language task. Because of the additional difficulty noted in AWS with word-medial targets, our results provide evidence of phonological encoding differences between the two groups. Expanded use of the PM paradigm is recommended for the exploration of additional aspects of language processing in people who stutter.

Selecting Treatments and Monitoring Outcomes: The Circle of Evidence-Based Practice and Client-Centered Care in Treating a Preschool Child Who Stutters.

Purpose: The purpose of the present clinical forum is to compare how 2 clinicians might select among therapy options for a preschool-aged child who presents with stuttering close to onset. Method: I discuss approaches to full evaluation of the child's profile, advisement of evidence-based practice options open to the family, the need for monitoring of the child's response, and selection of other approaches, if the child appears nonresponsive to the 1st-line approach. Results: Although some researchers and clinicians appear to favor endorsement of a single recommended treatment for early stuttering, I do not find this approach helpful or consistent with newer mandates for patient-centered care. I am also most comfortable recommending RESTART demands and capacities model as the 1st treatment approach, with parent consent, because its mechanism of action appears transparent and well-documented. Conclusions: There are numerous well-supported intervention options for treating preschool children who stutter. No single therapy can possibly work for all clients. I discuss available options that I feel have sufficient evidence-based support for use with young children who stutter. I emphasize the need to consider more, not fewer, acceptable therapy options for children who do not respond positively to a selected treatment approach within a reasonable time frame.

Fostering human rights through TalkBank.

In accord with articles 19 and 27 of the Universal Declaration of Human Rights, people with speech and language disorders have the right to receive maximal benefit from academic research on speech and language acquisition and disorders. To evaluate the diverse nature of speech and language disorders, this research must have access to large datasets, as well as to refined tools for the systematic analysis of these datasets. The TalkBank system addresses this need by providing researchers with thousands of hours of open-access database archives of digital audio, video and transcript files documenting typical and disordered language use in dozens of languages and cultures. In this paper, we review the TalkBank system, with an emphasis on the AphasiaBank, PhonBank and FluencyBank databases. We describe how specialised assessment tools can be used to study issues in speech and language acquisition and disorders recorded within these databases. We then provide illustrations of how assessments support the needs of researchers, clinicians, developers, and educators, whose combined work contributes solutions for people with speech, language and language learning disorders worldwide.

Preliminary Evidence That Growth in Productive Language Differentiates Childhood Stuttering Persistence and Recovery.

Purpose: Childhood stuttering is common but is often outgrown. Children whose stuttering persists experience significant life impacts, calling for a better understanding of what factors may underlie eventual recovery. In previous research, language ability has been shown to differentiate children who stutter (CWS) from children who do not stutter, yet there is an active debate in the field regarding what, if any, language measures may mark eventual recovery versus persistence. In this study, we examined whether growth in productive language performance may better predict the probability of recovery compared to static profiles taken from a single time point. Method: Productive syntax and vocabulary diversity growth rates were calculated for 50 CWS using random coefficient models. Logistic regression models were then used to determine whether growth rates uniquely predict likelihood of recovery, as well as if these rates were predictive over and above currently identified correlates of stuttering onset and recovery. Results: Different linguistic profiles emerged between children who went on to recover versus those who persisted. Children who had steeper productive syntactic growth, but not vocabulary diversity growth, were more likely to recover by study end. Moreover, this effect held after controlling for initial language ability at study onset as well as demographic covariates. Conclusions: Results are discussed in terms of how growth estimates can be incorporated in recommendations for fostering productive language skills among CWS. The need for additional research on language in early stuttering and recovery is suggested.

Input and uptake at 7 months predicts toddler vocabulary: the role of child-directed speech and infant processing skills in language development.

Both the input directed to the child, and the child's ability to process that input, are likely to impact the child's language acquisition. We explore how these factors inter-relate by tracking the relationships among: (a) lexical properties of maternal child-directed speech to prelinguistic (7-month-old) infants (N = 121); (b) these infants' abilities to segment lexical targets from conversational child-directed utterances in an experimental paradigm; and (c) the children's vocabulary outcomes at age 2;0. Both repetitiveness in maternal input and the child's speech segmentation skills at age 0;7 predicted language outcomes at 2;0; moreover, while these factors were somewhat inter-related, they each had independent effects on toddler vocabulary skill, and there was no interaction between the two.

Rate and phonological variation in preschool children: effects of modeling and directed influence.

PURPOSE: To explore the effect of modeling and explicit elicitation of slow and accurately produced speech in typically developing preschool children. Optional phonological reductions (e.g., deleted final stops) and changes in speech rate were examined in response to an adult conversational speaker's speech style. METHOD: Forty 3- and 4-year-olds (20 each) were tested in 3 tasks: (a) immediate repetition of a model, (b) spontaneous speech, and (c) directed speech style (cueing to correct "sloppy" speech). In Task 1, half of each group heard fast and hypoarticulated versus slow and hyperarticulated speech for a between-group response-to-model comparison. Tasks 2 and 3 were compared within subjects. RESULTS: Task 1 demonstrated that both age groups aligned with the speaker's rate and phonological variants usage when repeating a model. Tasks 2 and 3 revealed that 4-year-olds varied phonological reduction patterns according to the task demands, whereas 3-year-olds maintained consistent patterns of usage. In addition, neither group successfully realigned with the rapid speech rate in Task 3. CONCLUSIONS: These results contribute to an evidence base supporting the practice of modeling slow and clear speech to children with various production disorders. Further research is needed to explore the cognitive-linguistic processes underlying alignment before findings are applied to clinical populations.

Some pragmatic tips for dealing with clinical uncertainty.

PURPOSE: This article proposes some recommendations to enable clinicians to balance certainty and uncertainty when evaluating the currency and effectiveness of their treatment approaches. METHOD: I offer the following advice: (a) Question the authority of the information previously learned in one's career; (b) be cognizant of what we do not yet know about best clinical practice; (c) understand that knowledge of "best practices" is both temporary and relative; (d) enable access to new information by the use of electronic alerts; (e) be flexible in reading new clinical reports, keeping an open mind as to their value; (f) get the clinically relevant details of new approaches by reading the full reports; and (g) employ, and then evaluate the outcomes of, new approaches used in treating individuals on our caseload. RESULTS: Examples are provided to show that proactive participation in research-alert programs can enable clinicians to access emerging, clinically relevant information, some of which is controversial. Staying abreast of such information is more efficient than performing guided searches for information as challenging cases arise. CONCLUSIONS: Applications of these recommendations should enable practicing clinicians to entertain new, clinically useful concepts while not taxing the limited time that clinicians typically have to engage in continuing education.