Purpose: Behavior and temperament (e.g., emotional reactivity, self-regulation) have been considered relevant to stuttering and its developmental course, but the direction of this relation is still unknown. Knowledge of behavior difficulties and temperament in childhood stuttering can improve screening and intervention. The current study examined…

Purpose: Stuttering is a speech condition that can have a major impact on a person's quality of life. This descriptive study aimed to identify subgroups of people who stutter (PWS) based on stuttering burden and to investigate differences between these subgroups on psychosocial aspects of life. Method: The study included 618 adult participants who…

Purpose: The purpose of this meta-analytic study was to identify clinical characteristics, defined as child factors that can be assessed by a speech-language pathologist as part of a routine speech-language evaluation that may differentiate children who persist in stuttering from children who eventually recover from stuttering. Clinical…

Purpose: Behavioral genetic studies of speech fluency have focused on participants who present with clinical stuttering. Knowledge about genetic influences on the development and regulation of normal speech fluency is limited. The primary aims of this study were to identify the heritability of stuttering and high nonfluency and to assess the…

Purpose: Using a sample of 20,445 Dutch twins, this study examined the relationship between speech fluency and attentional regulation in children. A secondary objective was to identify etiological overlap between nonfluency and poor attention using fluency-discordant twin pairs. Method: Three fluency groups were created at age 5 using a parent…

Purpose: The purpose of this study was to determine whether the underlying temperamental structure of the Dutch Children's Behavior Questionnaire (CBQ; B. Van den Bergh & M. Ackx, 2003) was identical for children who stutter (CWS), typically developing children (TDC), and children with vocal nodules (CWVN). Method: A principal axis factor…

There is a need to evaluate the effectiveness of stuttering treatment programs delivered in domestic and international contexts and to determine if treatment delivered internationally is culturally sensitive. Evaluation of the effectiveness of the ISTAR Comprehensive Stuttering Program (CSP) within and across client groups from the Netherlands and…

Changes in upper/lower lip integrated electromyographic (IEMG) amplitude and temporal measures related to linguistic factors known for their influence on stuttering were investigated in 12 male Dutch nonstutterers. Findings indicated that production of stressed, vowel-rounding gestures of words in initial position, longer words, and words in…

A study of eight Dutch individuals (ages 14 to 56) who stutter found that adaptation of stuttering frequency during repeated readings may be a result of motor learning. Furthermore, during repeated readings, reductions in stuttering frequency were not related to reductions in the variability of acoustically derived measures of speech production.…