Publications by authors named "Stacy Shumway"

Restricted, repetitive and stereotyped patterns of behavior, interests and activities [RRBs] are among the core symptoms of autism spectrum disorders (ASD). Previous studies have indicated that RRBs differentiate ASD from other developmental disorders and from typical development. This study examined the presentation of RRBs as reported on the Repetitive Behavior Scale-Revised, a caregiver report, in children with ASD [separated into autism and Pervasive Developmental Disorder-Not Otherwise Specified groups] compared with children with nonspectrum developmental delays or typical development.

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Using two independent datasets provided by National Institute of Health funded consortia, the Collaborative Programs for Excellence in Autism and Studies to Advance Autism Research and Treatment (n = 641) and the National Institute of Mental Health (n = 167), diagnostic validity and factor structure of the new Autism Diagnostic Interview (ADI-R) algorithms for toddlers and young preschoolers were examined as a replication of results with the 2011 Michigan sample (Kim and Lord in J Autism Dev Disord 42(1): 82-93, 2012). Sensitivities and specificities and a three-factor solution were replicated. Results suggest that the new ADI-R algorithms can be appropriately applied to existing research databases with children from 12 to 47 months and down to nonverbal mental ages of 10 months for diagnostic grouping.

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Measurement of the severity of autism at a single time point, and over time, is a widespread challenge for researchers. Recently, Gotham, Pickles, and Lord published a severity metric (calibrated severity scores; CSS) that takes into account age and language level and is based on raw total scores of the Autism Diagnostic Observation Schedule (ADOS), a standardized measure commonly used in autism diagnosis. The present study examined psychometric characteristics of the CSS compared to raw scores in an independent sample of 368 children aged 2 to 12 years with autism, pervasive developmental disorder-not otherwise specified (PDD-NOS), non-spectrum delay, or typical development.

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This study examined the relationship between onset status and current functioning using a recently proposed onset classification system in 272 young children with autism spectrum disorder (ASD). Participants were classified into one of the following groups, based on parent report using the Autism Diagnostic Interview--Revised: Early Onset (symptoms by 12 months, no loss), Delay + Regression (symptoms by 12 months plus loss), Plateau (no early symptoms or loss), and Regression (no early symptoms, followed by loss). Findings indicate that current functioning does not differ according to onset pattern, calling into question the use of onset categorizations for prognostic purposes in children with ASD.

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Purpose: To examine the communicative profiles of children with autism spectrum disorders (ASD) in the second year of life.

Method: Communicative acts were examined in 125 children 18 to 24 months of age: 50 later diagnosed with ASD; 25 with developmental delays (DD); and 50 with typical development (TD). Precise measures of rate, functions, and means of communication were obtained through systematic observation of videotaped behavior samples from the Communication and Symbolic Behavior Scales Developmental Profile (A.

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Purpose: The purpose of this study was to examine the predictive validity of a collection of prelinguistic skills measured longitudinally in the 2nd year of life to language outcome in the 3rd year in children with typical language development.

Method: A collection of prelinguistic skills was assessed in 160 children early (M = 14.31 months; SD = 1.

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This study examined social communication profiles from behavior samples videotaped between 18 and 24 months of age in three groups of children: 50 with autism spectrum disorders (ASD), 23 with developmental delays (DD), and 50 with typical development (TD). The ASD group scored significantly lower than the DD group on 5 social communication measures and the TD group on all 14 measures, indicating distinct profiles late in the second year. Understanding was the strongest predictor of developmental level and behavior regulation and inventory of gestures were the strongest predictors of autism symptoms at 3 years of age.

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