The Childhood Autism Spectrum Test (CAST): Sex Differences

The Childhood Autism Spectrum Test (CAST) (formally known as the Childhood Asperger Screening Test) identifies autism spectrum conditions by measuring social and communication skills. The present study explored the sex distribution of scores. The CAST was distributed to 11,635 children aged 4–9 years in Cambridgeshire primary schools (UK). 3,370 (29%) were returned. The median score was significantly higher in boys (median test, P < 0.001) (Boys, median = 5 (IQR: 3,8); girls, median = 4 (IQR: 2,6)). There was a predominance of boys (n = 81 (79.4%) over girls (n = 21 (20.6%)) amongst those scoring ≥ 15. Exclusion of children with ASC did not significantly affect the results. We conclude that different profiles of social and communication skills in boys and girls must be taken into account when measuring these skills in the general population. Fiona Scott is now freelance.     

Psychometric Properties of the Mandarin Version of the Childhood Autism Spectrum Test (CAST): An Exploratory Study

Limited studies have investigated the latent autistic traits in the mainland Chinese population for autism spectrum conditions (ASC). This study explored the psychometric properties of a Mandarin Chinese version of the CAST in a sample consisting of 737 children in mainstream schools and 50 autistic cases. A combination of categorical data factor analysis and item response theory suggested a good-fit model of a two-factor solution for 28 items on the Mandarin CAST including social and communication, and inflexible/stereotyped language and behaviours (Goodness-of-fit indices: RMSEA = 0.029, CFI = 0.957, TLI = 0.950, SRMR = 0.064). The correlation between the two factors was moderate (GFC = 0.425). This study provided evidence for the CAST as a multidimensional measure for ASC screening in a Chinese population and also showed that the symptom manifestation of ASC in Chinese children shares similarity with western populations.     

Sex Differences in Autism Spectrum Disorder: a Review

Purpose of Review

Neurodevelopmental disorders disproportionately affect males. The mechanisms underlying male vulnerability or female protection are not known and remain understudied. Determining the processes involved is crucial to understanding the etiology and advancing treatment of neurodevelopmental disorders. Here, we review current findings and theories that contribute to male preponderance of neurodevelopmental disorders, with a focus on autism.

Recent Findings

Recent work on the biological basis of the male preponderance of autism and other neurodevelopmental disorders includes discussion of a higher genetic burden in females and sex-specific gene mutations or epigenetic changes that differentially confer risk to males or protection to females. Other mechanisms discussed are sex chromosome and sex hormone involvement. Specifically, fetal testosterone is involved in many aspects of development and may interact with neurotransmitter, neuropeptide, or immune pathways to contribute to male vulnerability. Finally, the possibilities of female underdiagnosis and a multi-hit hypothesis are discussed.

Summary

This review highlights current theories of male bias in developmental disorders. Topics include environmental, genetic, and epigenetic mechanisms; theories of sex chromosomes, hormones, neuroendocrine, and immune function; underdiagnosis of females; and a multi-hit hypothesis.

     

Sex Differences in Toddlers with Autism Spectrum Disorders

Although autism spectrum disorders (ASD) prevalence is higher in males than females, few studies address sex differences in developmental functioning or clinical manifestations. Participants in this study of sex differences in developmental profiles and clinical symptoms were 22 girls and 68 boys with ASD (mean age = 28 months). All children achieved strongest performance in visual reception and fine motor followed by gross motor and language functioning. Sex differences emerged in developmental profiles. Controlling for language, girls achieved higher visual reception scores than boys; boys attained higher language and motor scores and higher social-competence ratings than girls, particularly when controlling for visual reception. Longitudinal, representative studies are needed to elucidate the developmental and etiological significance of the observed sex differences.     

Comparison between a Mandarin Chinese version of the Childhood Autism Spectrum Test and the Clancy Autism Behaviour Scale in mainland China

A Mandarin Chinese version of the Childhood Autism Spectrum Test (CAST) and Clancy Autism Behaviour Scale (CABS) were applied to 150 children aged 4–11 years old from clinical settings and mainstream schools in Beijing. All the children were further assessed using the Autism Diagnostic Observation Schedule (ADOS) and the Autism Diagnostic Interview-Revised (ADI-R). The validity of two instruments on screening of ASC was examined and compared using receiver operating characteristic (ROC) curve analysis. The validity of CAST (sensitivity: 89%, specificity: 80%, PPV: 70%) was better than the CABS (sensitivity: 58%, specificity: 84%, PPV: 65%). The area under the curve (AUC) of the CAST (AUC = 0.90) was significantly higher than the CABS (AUC = 0.79, p = 0.0002). The Mandarin CAST demonstrated a better validity in distinguishing children with ASC from children without ASC. It is an acceptable candidate as a screening instrument for ASC in large epidemiological study in Chinese population.     

Convergent validity of the Autism Spectrum Disorder-Diagnostic for Children (ASD-DC) and Childhood Autism Rating Scales (CARS)

Previous studies analyzed the reliability as well as sensitivity and specificity of the Autism Spectrum Disorder-Diagnostic for Children (ASD-DC). This study further examines the psychometric properties of the ASD-DC by assessing whether the ASD-DC has convergent validity against a psychometrically sound observational instrument for Autistic Disorder. Thirty-seven children and adolescents, ages 3–14 years old were studied. Spearman's Rho was utilized to assess the convergent validity between the ASD-DC and the Childhood Autism Rating Scale (CARS). The ASD-DC and CARS total scores were compared. Additionally, the ASD-DC nonverbal communication, verbal communication, social relationships, and insistence on sameness/restricted interest factors were compared to the CARS items of nonverbal communication, verbal communication, relating to people, and adaptation to change. All correlation coefficients were statistically significant and ranged from .37 to .68, indicating that the ASD-DC demonstrated convergent validity against the CARS. Percent of correct classification was also computed for the ASD-DC and CARS as compared to diagnosis assigned for research purposes according to a checklist derived from the ICD-10 and DSM-IV criteria for autism spectrum disorders. On the ASD-DC, 76.5% correctly met cutoff for ASD and 95.0% were correctly classified as not meeting cutoff for an ASD. Of those meeting the cutoff on the CARS, 58.8% were correctly classified as having an ASD and 85.0% were correctly classified as not having ASD.     

Using the Autism Detection in Early Childhood (ADEC) and Childhood Autism Rating Scales (CARS) to Predict Long Term Outcomes in Children with Autism Spectrum Disorders

This study evaluated the predictive validity of the Autism Detection in Early Childhood (ADEC; Young, Autism detection in early childhood: ADEC. Australian Council of Educational Research, Camberwell, VIC 2007) and a well-established screening tool, the Childhood Autism Rating Scale (CARS; Schopler et al. The childhood autism rating scale (CARS). Western Psychological Services, Los Angeles 1988), for long term outcomes of children with ASD engaged in an early intervention program. Participants were 55 children (44 male, 11 female) aged 19–42 months (M = 33.5, SD = 5.6) at initial assessment who were followed up 2 and 6 years after their initial assessment. The ADEC and the CARS performed similarly when predicting long term outcomes such as clinical diagnostic outcome and overall adaptive functioning level. However, only the ADEC score was significantly correlated with ASD symptom severity at the 6-year follow up. Although these findings need to be replicated with additional and larger samples, this study extends our understanding of the psychometric properties of both the ADEC and the CARS.     

Sex Differences in Autism Spectrum Disorder: Evidence from a Large Sample of Children and Adolescents

Sex differences have been found amongst toddlers and young children with autism spectrum disorder (ASD). We investigated the presence and stability of these ASD sex differences throughout childhood and adolescence. Participants (N = 325, 52 females; aged 3-18 years) consecutively received an ASD diagnosis at a clinic for assessing high-functioning ASD (mean verbal IQ = 92.6). There were no IQ sex differences. By parent report and direct observation, females had less repetitive stereotyped behaviour (RSB), with male-equivalent levels of social and communication impairment. Teachers reported males with ASD as having greater externalising and social problems than females. The female phenotype we describe was stable across our sample's age range. Their milder RSBs and less severe difficulties at school may lead to under-recognition of ASD in females.     

Sex Differences in Functional Connectivity Between Resting State Brain Networks in Autism Spectrum Disorder

Journal of Autism and Developmental Disorders - Functional brain connectivity (FBC) has previously been examined in autism spectrum disorder (ASD) between-resting-state networks (RSNs) using a...     

Sex Differences in Children with Autism Spectrum Disorder Identified Within a High-Risk Infant Cohort

Sex differences were examined in 3-year-olds with autism spectrum disorders (ASD) ascertained from a high-risk cohort, and high- and low-risk comparison groups. Participants included 319 high-risk siblings and 129 low-risk controls. Eighty-five siblings were diagnosed with ASD, including 57 of 176 boys (32.4?%) and 28 of 143 girls (19.6?%), implying a relative odds of ASD of 1.65 in boys versus girls. There were modest sex differences on cognitive and adaptive skills and ASD symptom severity at age 3, but differences between boys and girls with ASD mirrored those in the non-ASD groups. The lower than expected male-to-female ratio, and the relatively high cognitive level among diagnosed children, suggest that we have identified an unanticipated number of higher-functioning girls with ASD.     

Sex Differences in Diagnosis and Clinical Phenotypes of Chinese Children with Autism Spectrum Disorder

The aim of this study was to explore the differences between boys and girls in the diagnosis and clinical phenotypes of autism spectrum disorder (ASD) in China's mainland. Children diagnosed with ASD (n = 1064, 228 females) were retrospectively included in the analysis. All children were assessed using the Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS). The results showed that girls scored significantly higher in ADI-R socio-emotional reciprocity than boys, and also scored lower in ADI-R and ADOS restricted and repetitive behaviors (RRBs). Meanwhile, the proportions of girls who satisfied the diagnostic cut-off scores in the ADI-R RRBs domain were lower than in boys (P < 0.05). Our results indicated that girls with ASD show greater socio-emotional reciprocity than boys. Girls also tended to show fewer RRBs than boys, and the type of RRBs in girls differ from those in boys. The ADI-R was found to be less sensitive in girls, particularly for assessment in the RRBs domain.     

Using the Childhood Autism Rating Scale to Diagnose Autism Spectrum Disorders

This study investigated the childhood autism rating scale (CARS) as a tool for ASD diagnoses for 2-year-old (n = 376) and 4-year-old (n = 230) children referred for possible autism. The cut-off score to distinguish autistic disorder from PDD-NOS was 32 in the 2-year-old sample (consistent with Lord in J Child Psychol Psychiatry Allied Discipl, 36, 1365–1382, 1995), and 30 in the 4-year-old sample, with good sensitivity and specificity at both ages. The cut-off score to distinguish ASD from non-ASD at both ages was 25.5, with good sensitivity and specificity. Results confirm the utility of the CARS in distinguishing autistic disorder from PDD-NOS, and distinguishing ASD from other developmental disorders and typical development and suggest that an ASD cutoff around 25, which is in common clinical use, is valid.     

Sex Differences in the Timing of Identification Among Children and Adults with Autism Spectrum Disorders

To examine differences by sex in the timing of identification of individuals with autism spectrum disorders (ASD), survey data were collected in the Netherlands from 2,275 males and females with autistic disorder, Asperger’s syndrome and PDD-NOS. Among participants <18 years of age, females with Asperger’s syndrome were identified later than males. Among participants ≥18 years of age, females with autistic disorder were identified later than males. In more recent years, girls with Asperger’s syndrome are diagnosed later than boys, confirming earlier findings. In adults, the delayed timing of diagnosis in females with autistic disorder may be related to changing practices in diagnosis over time. Strategies for changing clinician behaviour to improve recognition of ASD in females are needed.     

The Autism Diagnostic Interview-Revised and the Childhood Autism Rating Scale: Differences Between Diagnostic Systems and Comparison Between Genders

Diagnoses for autism based on the Autism Diagnostic Interview-Revised (ADI-R) and the Childhood Autism Rating Scale (CARS) were examined for 83 individuals with suspected autism. Agreement between systems reached 85.7%. Participants receiving diagnosis of autism based on only one system were significantly younger in age than individuals receiving diagnoses according to both systems. Individuals who did not receive diagnosis of autism on the ADI-R had lower chronological and mental ages and lower CARS scores compared to individuals who received diagnosis of autism based on the ADI-R. Eighteen females and 18 males were matched to examine possible gender differences. No significant findings were revealed, suggesting that the symptoms of autism according to the ADI-R and CARS do not differ between males and females when matched for chronological and mental ages.     

Brief Report: Adults with Mild Autism Spectrum Disorders (ASD): Scores on the Autism Spectrum Quotient (AQ) and Comorbid Psychopathology

While knowledge about symptom presentation of adults with mild ASD, including comorbid psychopathology, is limited, referral of adults with suspected mild PDD is increasing. We report on pilot research investigating whether patients diagnosed with mild ASD (n = 15) and patients who were not diagnosed with ASD (n = 21) differed in terms of (a) AQ scores and (b) Axis I and II disorders, assessed by the SCAN and the IPDE. Additionally, AQ scores were compared with those from non-ASD patients referred to a general outpatient clinic (n = 369). The results showed very few differences between ASD patients and non-ASD patients. Self-report may not differentiate mild ASD patients from non-ASD patients and Axis I and II disorders seem equally prevalent among these two groups.     

Parental Sleep Concerns in Autism Spectrum Disorders: Variations from Childhood to Adolescence

Sleep problems of adolescents and older children with Autism Spectrum Disorder (ASD) were compared to toddlers and young children in 1,859 children. Sleep was measured with the Children’s Sleep Habits Questionnaire. Total sleep problems were significant across all age groups, however the factors contributing to these problems differed. Adolescents and older children had more problems with delayed sleep onset, shorter sleep duration, and daytime sleepiness; while younger children had more bedtime resistance, sleep anxiety, parasomnias, and night wakings. The results suggest that sleep problems persist through adolescence in ASD with differences in types of problems experienced and emphasize the need for clinicians to address sleep behaviors not only in young children with ASD but throughout the age span.