Predicting Treatment Outcomes in Rapid Syllable Transition Treatment: An Individual Participant Data Meta-Analysis

Abstract

Purpose: The purpose of this study is to identify predictors of treatment outcomes in Rapid Syllable Transition Treatment (ReST) for childhood apraxia of speech through an individual participant data meta-analysis. Method: A systematic literature search identified nine ReST studies for inclusion. Individual participant data were obtained, and studies were coded for methodological design, baseline participant characteristics, service delivery factors, and treatment outcomes. Bivariate analyses were conducted to identify potential predictor variables. Multiple linear regressions were then performed to identify predictors of treatment outcomes. Results: Data for 36 participants from seven studies were included in the statistical analyses. In multivariate modeling, better performance on treated pseudowords posttreatment was predicted by higher baseline expressive language and Goldman-Fristoe Test of Articulation scores, lower speech inconsistency and percentage of vowels correct, and higher pretreatment accuracy on pseudoword targets. Better performance on untreated real words posttreatment was predicted by higher pretreatment accuracy on real words. Gains in performance and retention of gains were not significantly predicted by any individual variable or combination of variables. Conclusions: Baseline speech and expressive language skills and accuracy on pseudowords and real words were significant predictors of absolute posttreatment performance. Regardless of baseline characteristics, all children were statistically as likely to achieve gains during ReST and retain these gains for up to 4 weeks posttreatment. Large-scale prospective research is required to further examine the effects of dose frequency and co-occurring language impairments on treatment outcomes and the complex co-effects of percentage of vowels correct with other potential predictors. Supplemental Material: https://doi.org/10.23641/asha.19611714

A Pilot Randomized Control Trial of Motor-Based Treatments for Childhood Apraxia of Speech: Rapid Syllable Transition Treatment and Ultrasound Biofeedback

“…The sample size is not sufficiently large to determine whether there are predictors of individual factors that may indicate which children are best suited for either of these treatments. It should be noted that a recent individual participant data analysis of ReST studies ( Ng et al, 2022 ) has reported that baseline characteristics including, for example, better performance on treated nonsense words, higher expressive language and GFTA scores, and lower speech consistency and percent vowels correct predict absolute performance on treated nonsense words, whereas pretreatment performance on real words predicts performance post treatment on untreated real words. However, future research should be aimed at determining if measurable child-level factors can inform candidacy for ultrasound biofeedback and to compare suitability across treatments.…”