William Mandy

The Developmental, Dimensional and Diagnostic Interview (3Di): A Novel Computerized Assessment for Autism Spectrum Disorders.

OBJECTIVE Autism is a diagnostic spectrum of variable severity, with significant comorbidity. No existing standardized interview measures autistic features dimensionally. The authors aimed to develop a parental autism interview that could be administered to unselected clinical and general population samples that measures both symptom intensity and comorbidity across the full range of the autistic spectrum. METHOD A computerized procedure was devised for administration by trained interviewers that generates symptom and diagnostic profiles for both autism and non-autistic conditions. Test-retest reliability and interrater reliability were assessed in unselected clinical (n = 50) and nonclinical (n = 30) populations. Concurrent validity (n = 120), discriminant validity (n = 120), and criterion validity (n = 29) were evaluated in autistic spectrum and non-autistic patients. RESULTS Test-retest and interrater reliabilities were excellent (most intraclass correlation coefficients > 0.9). Concurrent validity (agreement with independent clinician formulation) was very good (mean kappa = 0.74). Criterion validity, a comparison with the Autism Diagnostic Interview, was excellent. Discrimination between autistic spectrum versus non-autistic subjects was almost perfect (sensitivity 1.0; specificity > 0.97). CONCLUSIONS The Developmental, Dimensional and Diagnostic Interview (3di) provides an efficient and accurate means of assessing, in dimensional terms, the presence of autistic symptoms in both clinical and normal populations. It offers novel opportunities for those engaged in research and clinical practice.

Social communication competence and functional adaptation in a general population of children: preliminary evidence for sex-by-verbal IQ differential risk.

OBJECTIVE The proportion of schoolchildren with mild social communicative deficits far exceeds the number diagnosed with an autistic spectrum disorder (ASD). We aimed to ascertain both the population distribution of such deficits and their association with functional adaptation and cognitive ability in middle childhood. METHOD The parent-report Social and Communication Disorders Checklist was administered to participants (n = 8,094) in the Avon Longitudinal Study of Parents and Children. We correlated impairment severity with independent clinical diagnoses of ASD, cognitive abilities, and teacher-rated maladaptive behavior. RESULTS Social and Communication Disorders Checklist scores were continuously distributed in the general population; boys had mean scores 30% higher than girls. Social communicative deficits were associated with functional impairment at school, especially in domains of hyperactivity and conduct disorders. A sex-by-verbal IQ interaction effect occurred: verbal IQ was protective against social communication impairments across the range of abilities in female subjects only. In male subjects, this protective effect did not exist for those with above-average verbal IQ. CONCLUSIONS Social communicative deficits are of prognostic significance, in terms of behavioral adjustment at school, for boys and girls. Their high general population prevalence emphasizes the importance of measuring such traits among clinically referred children who do not meet diagnostic ASD criteria. Above-average verbal IQ seems to confer protection against social communication impairments in female subjects but not in male subjects.

Research Review : What is the association between the social-communication element of autism and repetitive interests, behaviours and activities?

Autism is currently conceptualised as a unitary disorder, in which social-communication impairments are found alongside repetitive interests, behaviours and activities (RIBAs). This relies upon the validity of the assumption that social-communication impairments and RIBAs co-occur at an above chance level as a result of sharing underlying causes. In the current review it is argued that the evidence for this assumption is scarce: the very great majority of RIBA research has not been intended for or suited to its examination. In fact only three studies are fit to address directly the question of the relationship between social-communication impairment and RIBAs, and these contradict each other. In consequence, further relevant evidence was sought in the behavioural and genetic literature. This approach suggested that the correlation between social-communication impairments and RIBAs has been exaggerated in the current consensus about the autism syndrome, and that these aspects of autism may well share largely independent underlying causes. Some clinical and research implications are discussed.

Toward specifying Pervasive Developmental Disorder - Not Otherwise Specified

Pervasive developmental disorder—not otherwise specified (PDD‐NOS) is the most common and least satisfactory of the PDD diagnoses. It is not formally operationalized, which limits its reliability and has hampered attempts to assess its validity. We aimed, first, to improve the reliability and replicability of PDD‐NOS by operationalizing its DSM‐IV‐TR description and, second, to test its validity through comparison with autistic disorder (AD) and Aspergers disorder (AsD). In a sample of 256 young people (mean age = 9.1 years) we used Developmental, Diagnostic and Dimensional (3Di) algorithmic analysis to classify DSM‐IV‐TR AD (n = 97), AsD (n = 93) and PDD‐NOS (n = 66). Groups were compared on independent measures of core PDD symptomatology, associated autistic features, and intelligence. Contrary to the assumption that PDD‐NOS is heterogeneous, almost all (97%) of those with PDD‐NOS had one distinct symptom pattern, namely impairments in social reciprocity and communication, without significant repetitive and stereotyped behaviors (RSB). Compared to AD and AsD, they had comparably severe but more circumscribed social communication difficulties, with fewer non‐social features of autism, such as sensory, feeding and visuo‐spatial problems. These individuals appear to have a distinct variant of autism that does not merely sit at the less severe end of the same continuum of symptoms. The current draft guidelines for DSM‐V, which mandate the presence of RSBs for any PDD diagnosis, would exclude such people from the autistic spectrum. Autism Res 2011, 4: 121–131.

Meanings in motion and faces: Developmental associations between the processing of intention from geometrical animations and gaze detection accuracy

Aspects of face processing, on the one hand, and theory of mind (ToM) tasks, on the other hand, show specific impairment in autism. We aimed to discover whether a correlation between tasks tapping these abilities was evident in typically developing children at two developmental stages. One hundred fifty-four normal children (6-8 years and 16-18 years) and 13 high-IQ autistic children (11-17 years) were tested on a range of face-processing and IQ tasks, and a ToM test based on the attribution of intentional movement to abstract shapes in a cartoon. By midchildhood, the ability accurately and spontaneously to infer the locus of attention of a face with direct or averted gaze was specifically associated with the ability to describe geometrical animations using mental state terms. Other face-processing and animation descriptions failed to show the association. Autistic adolescents were impaired at both gaze processing and ToM descriptions, using these tests. Mentalizing and gaze perception accuracy are associated in typically developing children and adolescents. The findings are congruent with the possibility that common neural circuitry underlies, at least in part, processing implicated in these tasks. They are also congruent with the possibility that autism may lie at one end of a developmental continuum with respect to these skills, and to the factor(s) underpinning them.

Links Between Co-occurring Social-Communication and Hyperactive-Inattentive Trait Trajectories

Objective There is overlap between an autistic and hyperactive-inattentive symptomatology when studied cross-sectionally. This study is the first to examine the longitudinal pattern of association between social-communication deficits and hyperactive-inattentive symptoms in the general population, from childhood through adolescence. We explored the interrelationship between trajectories of co-occurring symptoms, and sought evidence for shared prenatal/perinatal risk factors. Method Study participants were 5,383 singletons of white ethnicity from the Avon Longitudinal Study of Parents and Children (ALSPAC). Multiple measurements of hyperactive-inattentive traits (Strengths and Difficulties Questionnaire) and autistic social-communication impairment (Social Communication Disorder Checklist) were obtained between 4 and 17 years. Both traits and their trajectories were modeled in parallel using latent class growth analysis (LCGA). Trajectory membership was subsequently investigated with respect to prenatal/perinatal risk factors. Results LCGA analysis revealed two distinct social-communication trajectories (persistently impaired versus low-risk) and four hyperactive-inattentive trait trajectories (persistently impaired, intermediate, childhood-limited and low-risk). Autistic symptoms were more stable than those of attention-deficit/hyperactivity disorder (ADHD) behaviors, which showed greater variability. Trajectories for both traits were strongly but not reciprocally interlinked, such that the majority of children with a persistent hyperactive-inattentive symptomatology also showed persistent social-communication deficits but not vice versa. Shared predictors, especially for trajectories of persistent impairment, were maternal smoking during the first trimester, which included familial effects, and a teenage pregnancy. Conclusions Our longitudinal study reveals that a complex relationship exists between social-communication and hyperactive-inattentive traits. Patterns of association change over time, with corresponding implications for removing exclusivity criteria for ASD and ADHD, as proposed for DSM-5.

High-Functioning Autism and Asperger's Disorder: Utility and Meaning for Families.

We used framework analysis to investigate the utility of pervasive developmental disorder diagnoses, interviewing young people (aged 9–16 years) with high-functioning autistic disorder (AD) and Asperger’s disorder (AsD), and their parents. Twenty two participants from ten families described both gains and costs resulting from diagnosis. Perceived advantages of AD and AsD diagnosis were increased understanding and practical support, and parental empowerment. Disadvantages included the effects of stigma and concerns about validity. Participants tended to consider AsD and AD as interchangeable terms. Findings suggest that the utility of AD and AsD depends upon both their validity and how these diagnoses are received in their cultural, economic and legislative context. Improvement of post-diagnostic services will improve the utility of AD and AsD.

The set-shifting profiles of anorexia nervosa and autism spectrum disorder using the Wisconsin Card Sorting Test: a systematic review and meta-analysis

Difficulties in set-shifting are commonly reported in both autism spectrum disorder (ASD) and anorexia nervosa (AN) populations. Despite this, it is not known whether this cognitive profile persists across different ages, or whether the profiles seen in ASD and AN are comparable. This systematic review and meta-analyses aimed to compare the set-shifting profiles, as measured by the Wisconsin Card Sorting Test (WCST) in adults and younger people with either ASD or AN, relative to healthy controls (HCs) and to statistically compare performance on the WCST between ASD and AN. In all, 24 studies on ASD and 22 studies on AN were identified. In ASD, there were significant differences between the clinical group and HCs, with the ASD group making significantly more perseverative errors, indicating greater difficulty in set-shifting [pooled effect size of d = 0.67, 95% confidence interval (CI) 0.53-0.81, p ⩽ 0.001]. This effect was consistent across the age span. For AN studies, there was a significant difference between adults with AN and HCs (d = 0.52, 95% CI 0.36-0.68, p ⩽ 0.001) but a non-significant effect in child studies (d = 0.25, 95% CI -0.05 to 0.55, z = 1.66, p = 0.096). Meta-regression indicated no effect of diagnosis (AN or ASD) on performance in adult studies but there was a non-significant trend (p = 0.053) towards children with ASD performing worse than children with AN. While difficulties with set-shifting appear to be stable in ASD, there may be differences between children and adults with AN, which warrant further investigation.

Investigating autism spectrum disorder and autistic traits in early onset eating disorder

OBJECTIVE To investigate whether young people (8-16 years) with an eating disorder have a higher prevalence of autism spectrum disorder (ASDs) and elevated autistic traits compared to typically developing (TD) peers. METHOD Twenty-two participants with early onset eating disorder (EOED) were assessed using standardized ASD measures and compared to IQ matched TD (n = 24) and ASD (n = 20) controls. RESULTS An ASD diagnosis was no more common in EOED than in TD controls. However, repetitive and stereotyped behavior was more often observed in the EOED group and, compared to TD controls, there was a trend (p = .07) toward greater autistic social impairment in EOED. DISCUSSION Whilst participants with EOED did not show increased ASD prevalence, they did have elevated autistic traits of clinical significance, particularly repetitive and stereotyped behavior. Further work is required to determine whether inflexibility and social difficulties in EOED have identical phenomenology and etiology to those seen in ASD.

Empirically based phenotypic profiles of children with pervasive developmental disorders: interpretation in the light of the DSM-5.

This study aimed to contribute to the Diagnostic and Statistical Manual (DSM) debates on the conceptualization of autism by investigating (1) whether empirically based distinct phenotypic profiles could be distinguished within a sample of mainly cognitively able children with pervasive developmental disorder (PDD), and (2) how profiles related to diagnoses and co-occurring behavioral and emotional problems. Six classes with distinct profiles were discerned. Three classes showed profiles not completely in line with the proposed DSM-5 conceptualization of autism. These classes included relatively many cognitively able individuals with PDD-not otherwise specified. However, profiles seemed to suit other diagnostic categories, such as social communication disorder. These alternative diagnoses could retain eligibility for services, and might adequately fit more specifically targeted interventions.