Purpose: Bayesian multilevel models are increasingly used to overcome the limitations of frequentist approaches in the analysis of complex structured data. This tutorial introduces Bayesian multilevel modeling for the specific analysis of speech data, using the brms package developed in R. Method: In this tutorial, we provide a practical…

Purpose: The purpose of this study is to quantify the interactions of the 3 vocalization subsystems of respiration, phonation, and resonance before, during, and after a perturbation to the larynx (temporarily induced unilateral vocal fold paralysis) in 10 vocally healthy participants. Using dynamic systems theory as a guide, we hypothesized that…

Purpose: A key goal of researchers, clinicians, and educators within the fields of speech, language, and hearing sciences is to support the learning and memory of others. To do so, they consider factors relevant to the individual, the material to be learned, and the training strategy that can maximize learning and retention. Statistical methods…

Purpose: Mounting evidence demonstrates deficits in children with specific language impairment (SLI) beyond the linguistic domain. Using meta-analysis, this study examined differences in children with and without SLI on tasks measuring inhibition and cognitive flexibility. Method: Databases were searched for articles comparing children (4-14…

Purpose: Research in communication sciences and disorders frequently involves the collection of clusters of observations, such as a series of scores for each individual receiving treatment over the course of an intervention study. However, little discipline-specific guidance is currently available on the subject of building and interpreting…

Purpose: The aim of this study was to determine whether extant language (lexical) knowledge or domain-general working memory is the better predictor of comprehension of object relative sentences for children with typical development. We hypothesized that extant language knowledge, not domain-general working memory, is the better predictor. Method:…

Purpose: Children who do not develop early literacy skills, especially phonological awareness (PA) and alphabet knowledge, prior to kindergarten are at risk for reading difficulties. We investigated a supplemental curriculum with children demonstrating delays in these skills. Method: A cluster randomized design with 104 preschool-age children in…

Purpose: Individual differences in vocabulary development may affect academic or social opportunities. It has been proposed that individual differences in word reading could affect the rate of vocabulary growth, mediated by the amount of reading experience, a process referred to as a "Matthew effect" (Stanovich, 1986). Method: In the…

Purpose: We describe the natural auditory environment of people with cochlear implants (CIs), how it changes across the life span, and how it varies between individuals. Method: We performed a retrospective cross-sectional analysis of Cochlear Nucleus 6 CI sound-processor data logs. The logs were obtained from 1,501 people with CIs (ages 0-96…

Purpose: This study used meta-analysis to investigate the difference in nonverbal cognitive test performance of children with specific language impairment (SLI) and their typically developing (TD) peers. Method: The meta-analysis included studies (a) that were published between 1995 and 2012 of children with SLI who were age matched (and not…

Purpose: This study investigated the etiology of late language emergence (LLE) in 24-month-old twins, considering possible twinning, zygosity, gender, and heritability effects for vocabulary and grammar phenotypes. Method: A population-based sample of 473 twin pairs participated. Multilevel modeling estimated means and variances of vocabulary and…

Purpose: This study investigated cumulative effects of language learning, specifically whether prior vocabulary knowledge or special education status moderated the effects of academic vocabulary instruction in high-poverty schools. Method: Effects of a supplemental intervention targeting academic vocabulary in first through third grades were…

Purpose: This research note explores the potential role of attention in mediating previously reported associations between language outcomes and prematurity. Method: As a follow-up investigation to Mahurin Smith, DeThorne, Logan, Channell, and Petrill (2014), we employed multilevel modeling to analyze longitudinal data on language and attention…

Purpose: The purpose of this study was to investigate the extent to which a parent-implemented language intervention improves language skills in toddlers at risk for persistent language impairment (LI) as compared with a group of typically developing toddlers. Method: Thirty-four children with LI between 24 and 42 months of age were randomly…

Purpose: The authors sought to determine whether a program of 5 weekly doses of milieu communication teaching (MCT) would yield improvements in children's communication and word use compared with a once-weekly delivery of the same treatment. Method: Sixty-four children with intellectual and communication delay were randomly assigned to receive…