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The Study to Explore Early Development (SEED) is a multi-site case-control study designed to explore the relationship between autism spectrum disorder (ASD) phenotypes and etiologies. The goals of this paper are to (1) describe the SEED algorithm that uses the Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS) to classify children with ASD, (2) examine psychometric properties of different ASD classification methods, including the SEED method that incorporates rules for resolving ADI-R and ADOS discordance, and (3) determine whether restricted interests and repetitive behaviors were noted for children who had instrument discordance resolved using ADI-R social and communication scores. Results support the utility of SEED criteria when well-defined groups of children are an important clinical or research outcome. [ABSTRACT FROM AUTHOR]

Background: Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, we know relatively little about the development of these differences in infancy. Methods: We used a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life. EEG was recorded at 6 and 12 months of age in infants at typical (N = 92) or elevated likelihood for ASD (N = 90), determined by the presence of an older sibling with ASD. We computed the functional connectivity between cortical sources of EEG during video watching using the corrected imaginary part of phase-locking values. Results: Our main analysis found no significant association between functional connectivity and ASD, showing only significant effects for age, sex, age-sex interaction, and site. Given these null results, we performed an exploratory analysis and observed, at 12 months, a negative correlation between functional connectivity and ADOS calibrated severity scores for restrictive and repetitive behaviors (RRB). Limitations: The small sample of ASD participants inherent to sibling studies limits diagnostic group comparisons. Also, results from our secondary exploratory analysis should be considered only as potential relationships to further explore, given their increased vulnerability to false positives. Conclusions: These results are inconclusive concerning an association between EEG functional connectivity and ASD in infancy. Exploratory analyses provided preliminary support for a relationship between RRB and functional connectivity specifically, but these preliminary observations need corroboration on larger samples. [ABSTRACT FROM AUTHOR]

With the increasing prevalence of Autism Spectrum Disorder (ASD) in recent years, there has been a significant interest in diagnostic accuracy and patterns of autism. Behavior checklists, such as the Autism Spectrum Rating Scale (ASRS), are widely used in psychological evaluations, and while some evidence supports their use in autism assessment, there is some question about their validity, especially when compared to comprehensive measures and behavioral observations. The current study used ADOS-2 diagnostic classifications as a measure of "ADOS-2 ASD" and compared this classification to ASRS parent and teacher ratings, with an aim of assessing the discriminant (diagnostic) validity of the ASRS. Analyses indicated that parent and teacher ASRS report scores were not significantly different for individuals with and without autism as indicated by ADOS-2 classification. Implications of this preliminary research as well as future directions are suggested, including a concern that the ASRS may not provide the specific information needed to assist clinicians in differentiating between children who do or do not meet ASD diagnostic criteria. [ABSTRACT FROM AUTHOR]

Objective: Although autism spectrum disorder (ASD) is a relatively common, well-known but heterogeneous neuropsychiatric disorder, specific knowledge about characteristics of this heterogeneity is scarce. There is consensus that IQ contributes to this heterogeneity as well as complicates diagnostics and treatment planning. In this study, we assessed the accuracy of the Autism Diagnostic Observation Schedule (ADOS/2) in the whole and IQ-defined subsamples, and analyzed if the ADOS/2 accuracy may be increased by the application of machine learning (ML) algorithms that processed additional information including the IQ level. Methods: The study included 1,084 individuals: 440 individuals with ASD (with a mean IQ level of 3.3 ± 1.5) and 644 individuals without ASD (with a mean IQ level of 3.2 ± 1.2). We applied and analyzed Random Forest (RF) and Decision Tree (DT) to the ADOS/2 data, compared their accuracy to ADOS/2 cutoff algorithms, and examined most relevant items to distinguish between ASD and Non-ASD. In sum, we included 49 individual features, independently of the applied ADOS module. Results: In DT analyses, we observed that for the decision ASD/Non-ASD, solely one to four items are sufficient to differentiate between groups with high accuracy. In addition, in sub-cohorts of individuals with (a) below (IQ level ≥4)/ID and (b) above average intelligence (IQ level ≤ 2), the ADOS/2 cutoff showed reduced accuracy. This reduced accuracy results in (a) a three times higher risk of false-positive diagnoses or (b) a 1.7 higher risk for false-negative diagnoses; both errors could be significantly decreased by the application of the alternative ML algorithms. Conclusions: Using ML algorithms showed that a small set of ADOS/2 items could help clinicians to more accurately detect ASD in clinical practice across all IQ levels and to increase diagnostic accuracy especially in individuals with below and above average IQ level. [ABSTRACT FROM AUTHOR]

This study aimed to investigate factors associated with a delayed autism spectrum (ASD) diagnosis when compared to children with either no or early ASD diagnosis. Among 893 children assessed for ASD before age 8, 39% had no ASD at baseline, of which 21% received a later ASD diagnosis. Autism symptoms, diagnostic history of other developmental disorders, cognitive ability, and socioeconomic factors were associated with delayed ASD. Autism Diagnostic Observation Schedule (ADOS) scores in delayed ASD fell between early and no ASD. Other developmental disorders, time and clinical trends like ADOS use and low parental education distinguished delayed and early ASD, whereas higher frequency of IQ < 70 at baseline and a diagnosis of emotional disorders during follow-up distinguished delayed and no ASD. [ABSTRACT FROM AUTHOR]

The present study aimed to explore clinical trends in the period 2000–2010, along with discriminating clinical factors for autism spectrum disorder (ASD), in young children suspected of ASD. The following trends were observed: (1) a rise in referrals including an increase in referrals among language-abled children, (2) an increase in children assigned an ASD diagnosis after assessment, and (3) a decrease in Autism Diagnostic Observation Schedule total score. The distribution of ASD subtypes and IQ level did not change. Results suggest that a higher proportion of children with less severe autism symptoms were referred and diagnosed. Further, restricted and repetitive behaviors seemed to be a key discriminating factor when distinguishing between ASD and no-ASD children with a discordant symptom profile. [ABSTRACT FROM AUTHOR]

Background: The Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) module four assessment for diagnosing autism spectrum disorder in adults has shown good sensitivity and specificity in research settings. Method: This study aimed to evaluate the predictive accuracy of the ADOS-2 module four by investigating the components of the assessment, in relation to diagnostic outcome in a clinical setting. Data from 88 service users referred to a Specialist Adult Autism Service was explored. Results: ADOS-2 scores failed to predict the diagnostic outcome (overall sensitivity = 92%, specificity = 57%). Interestingly, scores from the 'restricted interests' component of the ADOS-2 have the potential to predict diagnostic outcome, despite this domain not been included in the scoring algorithm. Conclusions: Based on our findings, we recommend clinicians are cautious when interpreting results of the ADOS-2 assessment. [ABSTRACT FROM AUTHOR]

Few measures are appropriate to assess autism symptoms in minimally verbal adolescents and adults. The Autism Diagnostic Observation Schedule, 2nd Edition (ADOS-2, Lord et al., in Autism diagnostic observation schedule–2nd edition (ADOS-2). Western Psychological Services, Los Angeles, 2012) Modules 1 and 2 were designed and validated with children whose spoken language ranges from few- to- no words to phrase speech. This study describes the development and initial validation of the Adapted-ADOS (A-ADOS), which includes tasks, materials and behavioral codes modified to be suitable for assessing older minimally verbal individuals. A-ADOS algorithms exhibit comparable sensitivity and improved specificity relative to ADOS-2 Modules 1 and 2. Although further validation is needed, the A-ADOS will facilitate research to further understanding of minimally verbal adults and symptom trajectories across the lifespan. [ABSTRACT FROM AUTHOR]

The Autism Diagnostic Observation Schedule (ADOS) is a widely utilized observational assessment tool for diagnosis of autism spectrum disorders. The original ADOS was succeeded by the ADOS-G with noted improvements. More recently, the ADOS-2 was introduced to further increase its diagnostic accuracy. Studies examining the validity of the ADOS have produced mixed findings, and pooled relationship trends between the algorithm versions are yet to be analyzed. The current review seeks to compare the relative merits of the ADOS-G and ADOS-2 algorithms, Modules 1-3. Eight studies met inclusion criteria for the review, and six were selected for paired comparisons of the sensitivity and specificity of the ADOS. Results indicate several contradictory findings, underscoring the importance of further study. [ABSTRACT FROM AUTHOR]

The Autism Diagnostic Observation Schedule (ADOS) is widely used to assess symptoms of autism spectrum disorder (ASD). Given well-documented differences in social behaviors across cultures, this study examined whether item-level biases exist in ADOS scores across sociodemographic groups (race, ethnicity, and gender). We examined a subset of ten ADOS items among participants (N = 2458). Holding level of overall ADOS behavioral symptoms constant, we found significant item level bias (measurement noninvariance) for race and ethnicity on three ADOS items. Item-level bias was not apparent across gender. Although the magnitude of bias was small, our findings highlight the need to reevaluate norms and operational definitions used in assessments to increase ASD diagnostic accuracy among culturally-diverse groups. [ABSTRACT FROM AUTHOR]

Prader-Willi syndrome (PWS), a rare genetic disorder caused by the lack of expression of paternal genes from chromosome 15q11-13, has been investigated for autism spectrum disorder (ASD) symptomatology in various studies. However, previous findings have been variable, and no studies investigating ASD symptomatology in PWS have exclusively studied children. We aimed to characterize social communication functioning and other ASD-related symptoms in children with PWS, and assessed agreement across measures and rates of ASD diagnosis. Measures included the Autism Diagnostic Observation Schedule-2 (ADOS-2), the Social Communication Questionnaire (SCQ), Social Responsiveness Scale-2 (SRS-2), Social Skills Improvement System-Rating Scales (SSIS-RS), and the Vineland Adaptive Behavioral Scales-II (VABS-II). General adaptive and intellectual skills were also assessed. Clinical best estimate (CBE) diagnosis was determined by an experienced developmental pediatrician, based on history and review of all available study measures, and taking into account overall developmental level. Participants included 10 children with PWS, aged 3 to 12 years. Three of the 10 children were male and genetic subtypes were two deletion (DEL) and eight uniparental disomy (UPD) (with a total of 6 female UPD cases). Although 8 of the 10 children exceeded cut-offs on at least one of the ASD assessments, agreement between parent questionnaires (SCQ, SRS-2, SSIS-RS) and observational assessment (ADOS-2) was very poor. None of the children were assigned a CBE diagnosis of ASD, with the caveat that the risk may have been lower because of the predominance of girls in the sample. The lack of agreement between the assessments emphasizes the complexity of interpreting ASD symptom measures in children with PWS. [ABSTRACT FROM AUTHOR]

Early language delay (ELD) is one of the earliest indicators of autism spectrum disorder (ASD), and predicts later cognitive and behavioral outcomes. We aimed to determine the neural correlates of ELD in autism, and examine the relationships between gray matter (GM), age of first word/phrase, and core ASD symptoms. We used voxel-based morphometry to examine whole-brain differences in GM in 8-13 year old children with autism ( n = 13 ELD; n = 22 non-ELD) and 35 age-matched typically developing (TD) children. Multiple regression analyses examined the relationships between GM, age of first word/phrase, and autism diagnostic observation schedule (ADOS) scores. Composite age of first word/phrase negatively correlated with GM throughout the cerebellum. Both ASD groups (ELD and non-ELD) had reduced GM in right cerebellar Crus I/II when compared to TD children. Left cerebellar Crus I/II was the only region in the brain that differentiated ELD and non-ELD children, with ELD children showing reduced GM relative to both non-ELD and TD groups. Group×score interactions converged in left Crus I/II, such that the non-ELD group showed poorer ADOS scores with increasing GM, whereas the ELD group showed poorer ADOS scores as GM decreased. Reduced GM in right cerebellar Crus I/I was related ASD diagnosis, while children with ELD showed additional reduced GM in left Crus I/II. These findings highlight the importance of specific cerebellar networks in both ASD and early language development, and suggest that bilateral disruption in cerebellar regions that interconnect with fronto-parietal networks could impact language acquisition in ASD. Autism Res 2016, 9: 1191-1204. © 2016 International Society for Autism Research, Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Changes to the DSM-5 Autism Spectrum Disorder (ASD) criteria raised concerns among parents and practitioners that the criteria may exclude some children with Pervasive Developmental Disorder (PDD). Few studies have examined DSM-5 sensitivity and specificity in children less than 5 years of age. This study evaluated 185 children aged 20-55 months with DSM-IV PDD or developmental delay. Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS) data was assigned to DSM-5 subdomains. Children displaying the required symptomatology were classified with DSM-5 ASD. DSM-IV clinical diagnoses were compared to DSM-5 classifications. Using combined ADI-R/ADOS information, sensitivity was .84 and specificity was .54. Comorbid behaviour and emotional problems were significantly lower in children with PDD that did not meet DSM-5 criteria. [ABSTRACT FROM AUTHOR]

Neurofibromatosis Type 1 (NF1) is a common autosomal dominant single-gene disorder, in which the co-occurrence of autism spectrum disorder (ASD) has attracted considerable research interest recently with prevalence estimates of 21-40 %. However, detailed characterization of the ASD behavioral phenotype in NF1 is still lacking. This study characterized the phenotypic profile of ASD symptomatology presenting in 4-16 year old children with NF1 (n = 36) using evidence from parent-rated Social Responsiveness Scale and researcher autism diagnostic observation Scale-2. Compared to IQ-matched reference groups of children with autism and ASD, the NF1 profile shows overall similarity but improved eye contact, less repetitive behaviors and better language skills. [ABSTRACT FROM AUTHOR]

Purpose: The Autism Diagnostic Observation Schedule (ADOS) contains a narrative generation task in which clients tell a story from a wordless picture book; however, the resulting narrative is not usually examined for its linguistic properties. This study aimed to examine narrative generation in autism spectrum disorder (ASD) by comparing narratives elicited from children with ASD during the ADOS to those produced by language-matched typically-developing (TD) peers. Method: Participants were children with ASD ( n = 11) and TD controls ( n = 17). Both groups were aged 9-15 years and were matched for expressive and receptive language skills and non-verbal intelligence. Narratives were analysed for local structure elements (length, fluency, errors, semantics and syntax), cohesion and global elements (story grammar and internal state language). Result: Results indicated that the narratives of the children with ASD were syntactically less complex, contained more ambiguous pronouns and included fewer story grammar elements than their control counterparts; with further analysis showing differences between younger and older children. Conclusion: The present findings provide evidence that children with ASD exhibit subtle story generation impairments and provide preliminary support for the inclusion of narratives elicited as part of the ADOS in the assessment of specific language skills in this population. [ABSTRACT FROM AUTHOR]

Atypical processing and integration of sensory inputs are hypothesized to play a role in unusual sensory reactions and social-cognitive deficits in autism spectrum disorder (ASD). Reports on the relationship between objective metrics of sensory processing and clinical symptoms, however, are surprisingly sparse. Here we examined the relationship between neurophysiological assays of sensory processing and (1) autism severity and (2) sensory sensitivities, in individuals with ASD aged 6-17. Multiple linear regression indicated significant associations between neural markers of auditory processing and multisensory integration, and autism severity. No such relationships were apparent for clinical measures of visual/auditory sensitivities. These data support that aberrant early sensory processing contributes to autism symptoms, and reveal the potential of electrophysiology to objectively subtype autism. [ABSTRACT FROM AUTHOR]