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OBJECTIVE: The purpose of this study is to present a set of empirically-derived effect size distributions to provide field-based benchmarks for interpreting the observed effects of interventions for young children on the autism spectrum, and for planning future studies. METHOD: We generated effect size distributions and reported quartile values for each by outcome domain, and by boundedness, proximity, and assessment approach using 1552 effect sizes from 144 early childhood autism intervention studies gathered for a previously published meta-analysis. RESULTS: Quartile values represent considerable heterogeneity in effect size distributions across outcome domains, as well as variability as a function of outcome boundedness, proximity, and assessment approach. CONCLUSIONS: Our results serve as field- and outcome-specific benchmarks (e.g., contextual guides for small, medium, large effects) that will help autism intervention researchers easily incorporate information from relevant prior empirical literature when conducting power analyses to plan for future studies. Benchmarks will also assist researchers seeking to interpret the magnitude of observed effects in clinical trials relative to the broader distribution of intervention effects on similar outcomes. Nuanced discussions that contextualize study findings in light of relevant empirical benchmarks will better assist practitioners in understanding the magnitude and scope of demonstrated change relative to studies with similar outcomes and selecting interventions for clinical practice. We discuss the limitations of these data, our analyses, as well as directions for future work.

OBJECTIVES. The present study examined whether remote microphone (RM) systems improved listening-in-noise performance in youth with autism. We explored effects of RM system use on both listening-in-noise accuracy and behaviorally measured listening effort in a well-characterized sample of participants with confirmed clinical diagnoses of autism. We hypothesized that listening-in-noise accuracy would be enhanced and listening effort reduced, on average, when participants used the RM system. Furthermore, we predicted that effects of RM system use on listening-in-noise accuracy and listening effort would vary according to participant characteristics. Specifically, we hypothesized that participants who were chronologically older, had greater nonverbal cognitive and language ability, displayed fewer features of autism, and presented with more typical sensory and multisensory profiles might exhibit greater benefits of RM system use than participants who were younger, had less nonverbal cognitive or language ability, displayed more features of autism, and presented with greater sensory and multisensory disruptions. DESIGN. We implemented a within-subjects design to investigate our hypotheses, wherein 32 youth with autism completed listening-in-noise testing with and without an RM system. Listening-in-noise accuracy and listening effort were evaluated simultaneously using a dual-task paradigm for stimuli varying in complexity (i.e., syllable-, word-, sentence-, and passage-level). In addition, several putative moderators of RM system effects (i.e., sensory and multisensory function, language, nonverbal cognition, and broader features of autism) on outcomes of interest were evaluated. RESULTS. Overall, RM system use resulted in higher listening-in-noise accuracy in youth with autism compared to no RM system use. The observed benefits were all large in magnitude, though the benefits on average were greater for more complex stimuli (e.g., key words embedded in sentences) and relatively smaller for less complex stimuli (e.g., syllables). Notably, none of the putative moderators significantly influenced the effects of the RM system on listening-in-noise accuracy, indicating that RM system benefits did not vary according to any of the participant characteristics assessed. On average, RM system use did not have an effect on listening effort across all youth with autism compared to no RM system use, but instead yielded effects that varied according to participant profile. Specifically, moderated effects indicated that RM system use was associated with (a) decreased listening effort for youth with average- to above-average nonverbal cognitive and language ability and (b) increased listening effort for youth who were less cognitively and linguistically able. CONCLUSIONS. This study extends prior work by showing that RM systems have the potential to boost listening-in-noise accuracy for youth with autism, as well as to reduce listening effort for youth with average to above-average cognitive and linguistic skills. In contrast, we found that, for those with below-average cognitive and linguistic skills, listening effort as indexed by reaction time increased with RM system use, perhaps suggesting greater engagement in the listening-in-noise tasks when using versus not using the RM system for this subgroup of youth with autism. These findings have important implications for clinical practice, suggesting RM system use in classrooms could potentially improve listening-in-noise performance for at least some youth with autism.

Purpose There is an ongoing need to develop assessments of spontaneous speech that focus on whether the child's utterances are comprehensible to listeners. This study sought to identify the attributes of a stable ratings-based measure of speech comprehensibility, which enabled examining the criterion-related validity of an orthography-based measure of the comprehensibility of conversational speech in students with Down syndrome. Method Participants were 10 elementary school students with Down syndrome and 4 unfamiliar adult raters. Averaged across-observer Likert ratings of speech comprehensibility were called a ratings-based measure of speech comprehensibility. The proportion of utterance attempts fully glossed constituted an orthography-based measure of speech comprehensibility. Results Averaging across 4 raters on four 5-min segments produced a reliable (G = .83) ratings-based measure of speech comprehensibility. The ratings-based measure was strongly ( r > .80) correlated with the orthography-based measure for both the same and different conversational samples. Conclusion Reliable and valid measures of speech comprehensibility are achievable with the resources available to many researchers and some clinicians.

Theory and research suggest that vocal development predicts "useful speech" in preschoolers with autism spectrum disorder (ASD), but conventional methods for measurement of vocal development are costly and time consuming. This longitudinal correlational study examines the reliability and validity of several automated indices of vocalization development relative to an index derived from human coded, conventional communication samples in a sample of preverbal preschoolers with ASD. Automated indices of vocal development were derived using software that is presently "in development" and/or only available for research purposes and using commercially available Language ENvironment Analysis (LENA) software. Indices of vocal development that could be derived using the software available for research purposes: (a) were highly stable with a single day-long audio recording, (b) predicted future spoken vocabulary to a degree that was nonsignificantly different from the index derived from conventional communication samples, and (c) continued to predict future spoken vocabulary even after controlling for concurrent vocabulary in our sample. The score derived from standard LENA software was similarly stable, but was not significantly correlated with future spoken vocabulary. Findings suggest that automated vocal analysis is a valid and reliable alternative to time intensive and expensive conventional communication samples for measurement of vocal development of preverbal preschoolers with ASD in research and clinical practice. Autism Res 2017, 10: 508-519. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.

We tested the relative levels (i.e., age equivalencies) of concurrent cross-modality (receptive and expressive) vocabulary and the relative strength of the longitudinal, cross-modality associations between early and later vocabulary sizes in minimally verbal preschoolers with ASD. Eighty-seven children participated. Parent-reported vocabulary was assessed at four periods separated by 4 months each. Expressive age equivalent scores were higher than receptive age equivalent scores at all four periods. Cross-lagged panel analysis was used to rule out common, but trivial, explanations for differences between the longitudinal associations of interest. Key associations were tested across intervals that varied from 8 to 12 months. In two of the three tested panels, the associations between early expressive vocabulary size and later receptive vocabulary size were stronger than the associations between early receptive vocabulary size and later expressive vocabulary size, providing evidence that is consistent with the hypothesis that expressive vocabulary size drives receptive vocabulary size in minimally verbal preschoolers with ASD.