This study assessed the utility of a brief assessment (the Peabody Picture Vocabulary Test-4th Edition; PPVT4) as a proxy for verbal IQ (VIQ) in large-scale studies of autism spectrum disorder (ASD). In a sample of 2,420 proband with ASD, PPVT4:IQ correlations were strong. PPVT4 scores were, on average, 5.
View Article and Find Full Text PDFJ Am Acad Child Adolesc Psychiatry
December 2016
Objective: Growing awareness that symptoms of autism spectrum disorder (ASD) transcend multiple diagnostic categories, and major advances in the identification of genetic syndromes associated with ASD, have led to widespread use of ASD symptom measures in etiologic studies of neurodevelopmental disorders. Insufficient consideration of potentially confounding factors such as cognitive ability or behavior problems can have important negative consequences in interpretation of findings, including erroneous estimation of associations between ASD and etiologic factors.
Method: Participants were 388 children 2 to 13 years old with diagnoses of ASD or another neurodevelopmental disorder without ASD.
Background: Minimally verbal (MV) children with autism spectrum disorder (ASD) are often assumed to be profoundly cognitively impaired and excluded from analyses due to challenges completing standardized testing protocols. A literature aimed at increasing understanding of this subgroup is emerging; however, the many methods used to define MV status make it difficult to compare studies. Understanding how different instruments and definitions used to identify MV children affect sample composition is critical to advance research on this understudied clinical population.
View Article and Find Full Text PDFThis study reports on the initial validation of the Autism Symptom Interview (ASI), School-Age, a brief (15-20 min) phone interview derived from questions from the Autism Diagnostic Interview-Revised (ADI-R). The ASI, School-Age was administered by interviewers with minimal training to parents of children ages 5 to 12 who had all been previously identified with (or referred for assessment of) ASD or another neurodevelopmental disorder. Children then underwent a comprehensive assessment to determine a best-estimate clinical diagnosis of ASD (n = 159) or non-ASD (e.
View Article and Find Full Text PDFRecent updates have been proposed to the Autism Diagnostic Observation Schedule-2 Module 4 diagnostic algorithm. This new algorithm, however, has not yet been validated in an independent sample without intellectual disability (ID). This multi-site study compared the original and revised algorithms in individuals with ASD without ID.
View Article and Find Full Text PDFDaily living skills (DLS), such as personal hygiene, meal preparation, and money management, are important to independent living. Research suggests that many individuals with autism spectrum disorder exhibit impairments in daily living skills relative to their cognitive skills. This study examined predictors of daily living skills attainment and trajectories of daily living skills in a longitudinal sample referred for possible autism spectrum disorder and followed from 2 to 21 years of age.
View Article and Find Full Text PDFStandardized calibrated severity scores (CSS) have been created for Autism Diagnostic Observation Schedule, 2nd edition (ADOS-2) Modules 1-4 as a metric of the relative severity of autism-specific behaviors. Total and domain CSS were created for the Toddler Module to facilitate comparison to other modules. Analyses included 388 children with ASD age 12-30 months and were replicated on 435 repeated assessments from 127 children with ASD.
View Article and Find Full Text PDFRaw totals from diagnostic and screening measures for autism spectrum disorder (ASD) are frequently used as dimensional measures of autism symptom severity without appropriate correction for confounding factors, such as developmental level or non-ASD-specific behavior problems. Although these associated features are important to consider when diagnosing ASD and developing intervention plans, both researchers and clinicians sometimes need metrics of ASD severity that are not influenced by these factors. The Autism Diagnostic Observation Schedule (ADOS) domain calibrated severity scores (CSS) were created to provide separate estimates of social affect (SA-CSS) and restricted, repetitive behaviors (RRB-CSS) that are relatively independent of child characteristics (Hus et al.
View Article and Find Full Text PDFWhole-exome sequencing (WES) studies have demonstrated the contribution of de novo loss-of-function single-nucleotide variants (SNVs) to autism spectrum disorder (ASD). However, challenges in the reliable detection of de novo insertions and deletions (indels) have limited inclusion of these variants in prior analyses. By applying a robust indel detection method to WES data from 787 ASD families (2,963 individuals), we demonstrate that de novo frameshift indels contribute to ASD risk (OR = 1.
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