Individuals with autism spectrum disorder and average IQ exhibit a widening discrepancy between lagging adaptive skills relative to their cognitive potential, but it is unknown when this discrepancy emerges in development. To address this important question, we measured adaptive and cognitive skills longitudinally, from 12-36 months, in 96…

Although the early behaviors associated with autism spectrum disorder have been well characterized, many behaviors are also commonly observed in young children with other developmental delays and even in those with typical development. Therefore, consideration must be given to whether a child demonstrates sufficient autism spectrum disorder…

We assessed potential factors associated with "current" or "ever" self-injurious behaviors, reported in the Autism Diagnostic Interview-Revised, among children with autism spectrum disorder (n = 692) from the Study to Explore Early Development. Data on factors examined were obtained from questionnaires, standardized clinical…

Children with autism spectrum disorder (ASD) tend to receive several related services during their early school years. In this study, we followed 70 preschoolers with ASD and used parent reports to document the intensity of these services over a 4-year period, in relation to children's outcomes in three domains. While behavioral difficulties…

Previously, we adapted the Home Situations Questionnaire to measure behavioral non-compliance in everyday settings in children with pervasive developmental disorders. In this study, we further revised this instrument for use in autism spectrum disorder and examined its psychometric properties (referred to as the Home Situations…

Unusual responses to sensory stimuli have been described in autism spectrum disorder (ASD).The study examined the frequencies of "unusual sensory interests" and "negative sensory responses" and their relation to functioning in a large ASD population (n = 679). Having "unusual sensory interests" was reported in 70.4%…

The Pervasive Developmental Disorder Behavior Inventory is a questionnaire designed to aid in the diagnosis of pervasive developmental disorders or autism spectrum disorders. The Pervasive Developmental Disorder Behavior Inventory assesses adaptive and maladaptive behaviors associated with pervasive developmental disorders and provides an…

Cross-informant ratings of are considered gold standard for child behavioral assessment. To date, little work has examined informant ratings of adaptive functioning for youth with autism spectrum disorder (ASD). In a large, diverse sample of youth with ASD, this study evaluated parent-teacher concordance of ratings of adaptive functioning and…

A gap exists in the literature regarding aggression in autism spectrum disorders and how this behavior compares to other groups. In this multisite study, the "Children's Scale for Hostility and Aggression: Reactive/Proactive" and the Aggression subscale of the "Child Behavior Checklist" were rated for 414 children with autism…

Mothers of children with autism report higher levels of depression than mothers of children with other developmental disabilities. We explored the relations between child characteristics of diagnostic severity and problem behaviors, parenting stress, relationship quality, and depressive symptoms in 70 mothers of young children with autism. We…

This prospective study of the FIRST WORDS® Project examined restricted and repetitive behaviors in a sample of 55 toddlers at a mean age of 20 months who were later diagnosed with autism spectrum disorder. Restricted and repetitive behaviors were coded using the Repetitive Movement and Restricted Interest Scales in two video-recorded observation…

Autism spectrum disorder and attention deficit hyperactivity disorder are neurodevelopmental disorders that cannot be codiagnosed under existing diagnostic guidelines ("Diagnostic and Statistical Manual of the American Psychiatric Association," 4th ed., text rev.). However, reports are emerging that attention deficit hyperactivity…

The purpose of this study was to examine the stability of mothers' perceptions of the negative impact of having a child with ASD in a sample of African American and Caucasian families as their children transitioned to early adolescence. Participants were mothers and children participating in an ongoing longitudinal study of children referred for…

The present quasi-experimental study examines the outcomes for a group of 102 children diagnosed with an autism spectrum disorder at age 2 who attended an inclusive toddler program (described by Stahmer and Ingersoll, 2004) until age 3. Outcomes on standardized developmental assessments indicate significant improvement, with large effect sizes, in…