Stability and change of IQ scores in preschool children diagnosed with autistic spectrum disorder

Concurrent validity of intelligence assessments in children with developmental disabilities in an Asian setting: Comparison of the Kaufman brief intelligence test - Second edition with the Wechsler Intelligence Scales

BACKGROUND

This study was carried out to compare the concurrent validity of the Kaufman Brief Intelligence Test - Second Edition (KBIT-2) with that of two Wechsler Intelligence Scales (Wechsler Intelligence Scale for Children - Fifth Edition (WISC-V) and the Wechsler Preschool and Primary Scale of Intelligence - Fourth Edition (WPPSI-IV)) in an Asian setting.

METHODS

A retrospective study reviewed the medical records of 101 children with developmental disorders who were being followed up at a tertiary child development unit. Pearson product moment correlation coefficients were calculated between the KBIT-2 and Wechsler assessment scores. Simple regression analysis was used to calculate standard errors of estimation to assess the accuracy of predicting Wechsler scores using KBIT-2 scores.

RESULTS

A strong positive correlation was observed between KBIT-2's Intelligence Quotient (IQ) Composite and WISC-V's Full-Scale IQ (FSIQ) scores (r = 0.722, p < 0.01). KBIT-2 IQ composite scores showed a moderately strong positive correlation with WPPSI-IV FSIQ scores (r = 0.648, p < 0.01). Simple regression analysis showed that KBIT-2 scores tended to underestimate or overestimate the Wechsler scores, with the highest variability seen in KBIT-2's Non-Verbal IQ and Wechsler's Fluid Reasoning Index scores (error limits: -53.1 to 39.7).

CONCLUSION

Our study demonstrates that KBIT-2 has good concurrent validity when compared to other IQ tests such as the Wechsler scales, and it suggests that KBIT-2 is a good screening tool for assessing intelligence in a group of children with developmental disabilities. Further studies are needed to determine whether KBIT-2 can be used for the purpose of diagnostic decision-making or special education program placement.

Visual abilities and exploration behaviors as predictors of intelligence in autistic children from preschool to school age

LAY ABSTRACT

At the time of diagnosis, parents of autistic children frequently wonder what the future holds for their children in terms of intellectual development. It remains however difficult to answer this question at such a young age. Indeed, while early precursors of intelligence are well known for children following a typical development, these precursors remain to be identified for autistic children. Some theoretical models of intelligence suggest that perceptual abilities or behaviors, as seen early in autistic cognitive development, could be early indicators of intelligence. However, research examining the relation between early perceptual predictors and autistic intelligence over time is needed. This article is the first to consider a variety of early perceptual abilities and behaviors as precursors/predictors of intelligence at school age in autistic children. We showed that better performance in perceptual tasks at preschool age predicted better intellectual abilities measured later in autistic children. Importantly, our sample of autistic children represented the whole spectrum, including children with few to no spoken words, who are an important proportion of autistic preschoolers. While early perceptual abilities and behaviors may not substitute for a formal intellectual assessment, our results support that these indices may help estimate later intellectual level in autistic children. Perceptual abilities have the advantage to be easy to observe at preschool age and seem to fit the cognitive style of autistic children. Assessment methods could probably gain from including and focusing more on the perceptual strengths of autistic children.

Classification of Preschoolers with Low-Functioning Autism Spectrum Disorder Using Multimodal MRI Data

Multimodal imaging studies targeting preschoolers and low-functioning autism spectrum disorder (ASD) patients are scarce. We applied machine learning classifiers to parameters from T1-weighted MRI and DTI data of 58 children with ASD (age 3-6 years) and 48 typically developing controls (TDC). Classification performance reached an accuracy, sensitivity, and specificity of 88.8%, 93.0%, and 83.8%, respectively. The most prominent features were the cortical thickness of the right inferior occipital gyrus, mean diffusivity of the middle cerebellar peduncle, and nodal efficiency of the left posterior cingulate gyrus. Machine learning-based analysis of MRI data was useful in distinguishing low-functioning ASD preschoolers from TDCs. Combination of T1 and DTI improved classification accuracy about 10%, and large-scale multi-modal MRI studies are warranted for external validation.

Oxytocin Exposure in Labor and its Relationship with Cognitive Impairment and the Genetic Architecture of Autism

Whether there is a relationship between oxytocin (OXT) use in labor and the risk of autism (ASD), and the nature of such relationship, is unclear. By integrating genetic and clinical data in a sample of 176 ASD participants, we tested the hypothesis that OXT is a marker for abnormal prenatal development which leads to impairments in the process of labor. OXT-exposed ASD had more obstetric complications (P = 0.031), earlier onset of symptoms (P = 0.027), poorer cognitive development (P = 0.011), higher mutation burden across neurodevelopment genes (P = 0.020; OR = 5.33) and lower transmission of polygenic risk for ASD (P = 0.0319), than non-exposed ASD. OXT seems to constitute a risk indicator rather than a risk factor for ASD, which is relevant for diagnostic and genetic counselling.

Overall prognosis of preschool autism spectrum disorder diagnoses

BACKGROUND

Autism spectrum disorder is a neurodevelopmental disorder characterised by social communication difficulties, restricted interests and repetitive behaviours. The clinical pathway for children with a diagnosis of autism spectrum disorder is varied, and current research suggests some children may not continue to meet diagnostic criteria over time.

OBJECTIVES

The primary objective of this review was to synthesise the available evidence on the proportion of preschool children who have a diagnosis of autism spectrum disorder at baseline (diagnosed before six years of age) who continue to meet diagnostic criteria at follow-up one or more years later (up to 19 years of age).

SEARCH METHODS

We searched MEDLINE, Embase, PsycINFO, and eight other databases in October 2017 and ran top-up searches up to July 2021. We also searched reference lists of relevant systematic reviews.

SELECTION CRITERIA

Two review authors independently assessed prospective and retrospective follow-up studies that used the same measure and process within studies to diagnose autism spectrum disorder at baseline and follow-up. Studies were required to have at least one year of follow-up and contain at least 10 participants. Participants were all aged less than six years at baseline assessment and followed up before 19 years of age.

DATA COLLECTION AND ANALYSIS

We extracted data on study characteristics and the proportion of children diagnosed with autism spectrum disorder at baseline and follow-up. We also collected information on change in scores on measures that assess the dimensions of autism spectrum disorder (i.e. social communication and restricted interests and repetitive behaviours). Two review authors independently extracted data on study characteristics and assessed risk of bias using a modified quality in prognosis studies (QUIPS) tool. We conducted a random-effects meta-analysis or narrative synthesis, depending on the type of data available. We also conducted prognostic factor analyses to explore factors that may predict diagnostic outcome.

MAIN RESULTS

In total, 49 studies met our inclusion criteria and 42 of these (11,740 participants) had data that could be extracted. Of the 42 studies, 25 (60%) were conducted in North America, 13 (31%) were conducted in Europe and the UK, and four (10%) in Asia. Most (52%) studies were published before 2014. The mean age of the participants was 3.19 years (range 1.13 to 5.0 years) at baseline and 6.12 years (range 3.0 to 12.14 years) at follow-up. The mean length of follow-up was 2.86 years (range 1.0 to 12.41 years). The majority of the children were boys (81%), and just over half (60%) of the studies primarily included participants with intellectual disability (intelligence quotient < 70). The mean sample size was 272 (range 10 to 8564). Sixty-nine per cent of studies used one diagnostic assessment tool, 24% used two tools and 7% used three or more tools. Diagnosis was decided by a multidisciplinary team in 41% of studies. No data were available for the outcomes of social communication and restricted and repetitive behaviours and interests. Of the 42 studies with available data, we were able to synthesise data from 34 studies (69% of all included studies; n = 11,129) in a meta-analysis. In summary, 92% (95% confidence interval 89% to 95%) of participants continued to meet diagnostic criteria for autism spectrum disorder from baseline to follow-up one or more years later; however, the quality of the evidence was judged as low due to study limitations and inconsistency. The majority of the included studies (95%) were rated at high risk of bias. We were unable to explore the outcomes of change in social communication and restricted and repetitive behaviour and interests between baseline and follow-up as none of the included studies provided separate domain scores at baseline and follow-up. Details on conflict of interest were reported in 24 studies. Funding support was reported by 30 studies, 12 studies omitted details on funding sources and two studies reported no funding support. Declared funding sources were categorised as government, university or non-government organisation or charity groups. We considered it unlikely funding sources would have significantly influenced the outcomes, given the nature of prognosis studies.

AUTHORS' CONCLUSIONS

Overall, we found that nine out of 10 children who were diagnosed with autism spectrum disorder before six years of age continued to meet diagnostic criteria for autism spectrum disorder a year or more later, however the evidence was uncertain. Confidence in the evidence was rated low using GRADE, due to heterogeneity and risk of bias, and there were few studies that included children diagnosed using a current classification system, such as the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) or the eleventh revision of the International Classification of Diseases (ICD-11). Future studies that are well-designed, prospective and specifically assess prognosis of autism spectrum disorder diagnoses are needed. These studies should also include contemporary diagnostic assessment methods across a broad range of participants and investigate a range of relevant prognostic factors.

Examination of professional biases about autism: how can we do better?

This paper lends a critical eye to six common assumptions/biases about autism that may influence neuropsychologists in their clinical work. These biases are based on research as well as the historical roots of the study of autism. Our goal is to encourage curiosity and reflection on these biases in order to improve neuropsychological service delivery for people on the autism spectrum. Methods: We argue that psychologists should strive to understand the function of behaviours observed with autism in order to offer helpful supports. We explore the assertions that autism is not a dichotomous or linear construct and that the use of high and low functioning descriptors are not useful nor appreciated by the autism community. We discuss the widely held beliefs that individuals on the autism spectrum lack theory of mind, empathy and social motivation. Importantly, people on the autism spectrum are telling us that the dialogue about them around theory of mind and empathy is a human rights issue. Finally, we discuss the role of standardized testing. Conclusions: Through an exploration of research literature, the writings of scholars and advocates on the autism spectrum, and personal, clinical and research experience we encourage our profession to take a leadership role in examining biases and changing the clinical and research landscape so that it better reflects respectful discourse for individuals on the autism spectrum. This is critical to reduce the stigma that continues to be associated with autism and has a negative affect on mental health and quality of life.

Do Biological Sex and Early Developmental Milestones Predict the Age of First Concerns and Eventual Diagnosis in Autism Spectrum Disorder?

Despite advances in early detection, the average age of autism spectrum disorder (ASD) diagnosis exceeds 4 years and is often later in females. In typical development, biological sex predicts inter-individual variation across multiple developmental milestones, with females often exhibiting earlier progression. The goal of this study was to examine sex differences in caregiver-reported developmental milestones (first word, phrase, walking) and their contribution to timing of initial concerns expressed by caregivers and eventual age of diagnosis. 195 (105 males) children and adolescents aged 8 to 17 years with a clinical diagnosis of ASD were recruited to the study (mean IQ = 99.76). While developmental milestones did not predict timing of diagnosis or age parents first expressed concerns, females had earlier first words and phrases than males. There was a marginal difference in the age of diagnosis, with females receiving their diagnosis 1 year later than males. Despite sex differences in developmental milestones and diagnostic variables, IQ was the most significant predictor in the timing of initial concerns and eventual diagnosis, suggesting children with lower IQ, regardless of sex, are identified and diagnosed earlier. Overall, biological sex and developmental milestones did not account for a large proportion of variance for the eventual age of ASD diagnosis, suggesting other factors (such as IQ and the timing of initial concerns) are potentially more influential. LAY SUMMARY: In this study, a later age of diagnosis in females having ASD was confirmed; however, biological sex was not the stronger predictor of age of diagnosis. Parents reported that females learned language more quickly than males, and parents noted their first concerns when females were older than males. In this sample, the strongest predictor of age of diagnosis was the age of first concerns.

The complexity of early diagnostic decision making: A follow-up study of young children with language difficulties

Background & aims

Due to the complexity of early diagnostic decision making, we examined the predictive value of an early diagnostic classification and early abilities on later best estimate diagnosis for 22 clinically referred children with language difficulties.

Methods and procedures

Four years after initial evaluation (Time 1), the clinical files of these children were reviewed. A best-estimate (BE) diagnosis of language disorder (LD), intellectual disability (ID), or autism spectrum disorder (ASD) was established, with ASD being most common.

Outcomes and results

Early clinical classifications were relatively unstable or difficult to establish at a young age. The magnitude of children's cognitive and receptive language delay was a significant predictor of a later BE diagnosis of ID and LD respectively. A BE diagnosis of ASD, by contrast, could not be predicted from children's early social communication problems nor the presence of restricted and repetitive behaviors and interests.

Conclusions

Taken together, the results of this study suggest that language difficulties can be an early marker of a neurodevelopmental disorder which is often not identified at the age of first referral.

Implications

Eligibility for treatment should, therefore, be based on biopsychosocial case formulation rather than DSM or ICD diagnostic classification.

What this paper adds?

In this study a dimensional approach was used to characterize the abilities of young children referred with mild to profound receptive and/or expressive language difficulties. Later on, a categorical approach was adopted to establish best estimate diagnoses. Our clinical, broadly defined sample reflects the heterogeneous intake of young children referred for diagnostic assessment. Other studies on diagnostic stability often only focus on one diagnostic category (and are explicitly excluding children with specific other diagnoses), not taking into account the difficulties of early differential diagnostic decision making and stability across different categories over time. Investigations of differential diagnosis within a clinical group, instead of only differentiating children with a specific diagnosis from typically developing children, may be more informative for clinicians.

Trajectories in Symptoms of Autism and Cognitive Ability in Autism From Childhood to Adult Life: Findings From a Longitudinal Epidemiological Cohort

OBJECTIVE

For the first time, we use a longitudinal population-based autism cohort to chart the trajectories of cognition and autism symptoms from childhood to early adulthood and identify features that predict the level of function and change with development.

METHOD

Latent growth curve models were fitted to data from the Special Needs and Autism Project cohort at three time points: 12, 16, and 23 years. Outcome measures were IQ and parent-reported Social Responsiveness Scale autism symptoms. Of the 158 participants with an autism spectrum disorder at 12 years, 126 (80%) were reassessed at 23 years. Child, family, and contextual characteristics obtained at 12 years predicted intercept and slope of the trajectories.

RESULTS

Both trajectories showed considerable variability. IQ increased significantly by a mean of 7.48 points from 12 to 23 years, whereas autism symptoms remained unchanged. In multivariate analysis, full-scale IQ was predicted by initial language level and school type (mainstream/specialist). Participants with a history of early language regression showed significantly greater IQ gains. Autism symptoms were predicted by Social Communication Questionnaire scores (lifetime version) and emotional and behavioral problems. Participants attending mainstream schools showed significantly fewer autism disorder symptoms at 23 years than those in specialist settings; this finding was robust to propensity score analysis for confounding.

CONCLUSION

Our findings suggest continued cognitive increments for many people with autism across the adolescent period, but a lack of improvement in autism symptoms. Our finding of school influences on autism symptoms requires replication in other cohorts and settings before drawing any implications for mechanisms or policy.

Cognition After Early Tonsillectomy for Mild OSA

OBJECTIVES

It remains uncertain whether treatment with adenotonsillectomy for obstructive sleep apnea in children improves cognitive function. The Preschool Obstructive Sleep Apnea Tonsillectomy and Adenoidectomy study was a prospective randomized controlled study in which researchers evaluated outcomes 12 months after adenotonsillectomy compared with no surgery in preschool children symptomatic for obstructive sleep apnea.

METHODS

A total of 190 children (age 3-5 years) were randomly assigned to early adenotonsillectomy (within 2 months) or to routine wait lists (12-month wait, no adenotonsillectomy [NoAT]). Baseline and 12-month assessments included cognitive and behavioral testing, medical assessment, polysomnography, and audiology. The primary outcome was global IQ at 12-month follow-up, measured by the Woodcock Johnson III Brief Intellectual Ability (BIA). Questionnaires included the Pediatric Sleep Questionnaire, Parent Rating Scale of the Behavioral Assessment System for Children-II, and Behavior Rating Inventory of Executive Function, Preschool Version.

RESULTS

A total of 141 children (75.8%) attended baseline and 12-month assessments, and BIA was obtained at baseline and 12-month follow-up for 61 and 60 participants in the adenotonsillectomy versus NoAT groups, respectively. No cognitive gain was found after adenotonsillectomy compared with NoAT, adjusted for baseline; BIA scores at 12-month follow-up were as follows: adenotonsillectomy, 465.46 (17.9) versus NoAT, 463.12 (16.6) (mean [SD]). Improvements were seen for polysomnogram arousals and apnea indices and for parent reports of symptoms (Pediatric Sleep Questionnaire), behavior (Behavior Assessment System for Children behavioral symptoms, P = .04), overall health, and daytime napping.

CONCLUSIONS

Structured testing showed no treatment-attributable improvement in cognitive functioning of preschool children 12 months after adenotonsillectomy compared with NoAT. Improvements were seen after adenotonsillectomy in sleep and behavior by using polysomnogram monitoring and parental questionnaires.

Developmental Trajectories of Feeding Problems in Children with Autism Spectrum Disorder

OBJECTIVE

Although feeding problems are a common concern in children with autism spectrum disorder (ASD), few longitudinal studies have examined their persistence over time. The purpose of this study was to examine the developmental progression of feeding problems across four time points in preschoolers with ASD.

METHODS

Group-based trajectory analyses revealed four distinct trajectories of feeding problems in our sample (N = 396).

RESULTS

The majority of children showed levels of feeding problems that were low from the outset and stable (Group 1; 26.3%) or moderate and declining over time (Group 2; 38.9%). A third group (26.5%) showed high levels of feeding problems as preschoolers that declined to the average range by school age. Few participants (8.3%) showed evidence of severe chronic feeding problems. Feeding problems were more highly correlated with general behavior problems than with autism symptom severity.

CONCLUSIONS

Overall, our findings demonstrated that in our sample of children with ASD, most feeding problems remitted over time, but a small subgroup showed chronic feeding problems into school age. It is important to consider and assess feeding problems in ASD against the backdrop of typical development, as many children with ASD may show improvement with age.

Maternal Interactive Behaviours in Parenting Children with Williams Syndrome and Autism Spectrum Disorder: Relations with Emotional/Behavioural Problems

This study compared maternal responsiveness to children with two neurodevelopmental disorders sharing different but, in some cases, overlapping social phenotypes-Williams syndrome (WS) and autism spectrum disorder (ASD)-and explored the relations between maternal responsiveness and child emotional/behavioural problems (EBP). The sample included 16 pre-schoolers with WS and 43 with ASD, and their mothers. Responsiveness was assessed during a mother-child interaction task. Mothers completed the CBCL 1½-5, providing a measure of EBP. No significant differences emerged between groups, and most dyads were characterized by less responsive behaviours. Maternal responsiveness proved related to child developmental age, but not with EBP. These results provide further insight into the rearing environment of children with neurodevelopmental disorders, highlighting the need for early relationship-based interventions.

Young children who screen positive for autism: Stability, change and "comorbidity" over two years

BACKGROUND

Autism spectrum disorder (ASD) is a developmental disorder with a wide variety of clinical phenotypes and co-occurrences with other neurodevelopmental conditions. Symptoms may change over time.

AIMS

The aim of the present study was to prospectively follow 96 children, initially assessed for suspected ASD at an average age of 2.9 years.

METHODS AND PROCEDURES

All children had been identified with autistic symptoms in a general population child health screening program, and had been referred to the Child Neuropsychiatry Clinic in Gothenburg, Sweden for further assessment by a multi-professional team at Time 1 (T1). This assessment included a broad neurodevelopmental examination, structured interviews, a cognitive test and evaluations of the child́s adaptive and global functioning. Two years later, at Time 2 (T2), the children and their parents were invited for a follow-up assessment by the same team using the same methods.

OUTCOMES AND RESULTS

Of the 96 children, 76 had met and 20 had not met full criteria for ASD at T1. Of the same 96 children, 79 met full ASD criteria at T2. The vast majority of children with ASD also had other neurodevelopmental symptoms or diagnoses. Hyperactivity was observed in 42% of children with ASD at T2, and Intellectual Developmental Disorder in 30%. Borderline Intellectual Functioning was found in 25%, and severe speech and language disorder in 20%. The children who did not meet criteria for ASD at T2 had symptoms of or met criteria for other neurodevelopmental/neuropsychiatric disorders in combination with marked autistic traits. Changes in developmental profiles between T1 and T2 were common in this group of young children with ASD. The main effect of Cognitive level at T1 explained more than twice as much of the variance in Vineland scores as did the ASD subtype; children with IDD had significantly lower scores than children in the BIF and AIF group. Co-existence with other conditions was the rule.

CONCLUSIONS AND IMPLICATIONS

Reassessments covering the whole range of these conditions are necessary for an optimized intervention-adapted to the individual child's needs.

Stability and Change in the Cognitive and Adaptive Behaviour Scores of Preschoolers with Autism Spectrum Disorder

We examined the stability of cognitive and adaptive behaviour standard scores in children with autism spectrum disorder (ASD) between diagnosis and school entry approximately age 6. IQ increased 18 points in 2-year-olds, 12 points in 3-year-olds, and 9 points in 4-year-olds (N = 281). Adaptive behaviour scores increased 4 points across age groups (N = 289). At school entry, 24 % of children met criteria for intellectual disability (cognitive and adaptive behaviour scores <70). No children with both scores ≥70 at diagnosis later met criteria for intellectual disability. Outcomes were more variable for children with initial delays in both areas (in 57 %, both scores remained <70). Findings are relevant to clinical decision-making, including specification of intellectual disability in young children with ASD.

Cognitive development in children with language impairment, and correlation between language and intelligence development in kindergarten children with developmental delay

We performed a retrospective review of 65 children with developmental delay. The male-to-female ratio was 2.25 : 1, and the mean age was 5.8 years; performance IQ was 94.8, verbal IQ was 83, and full-scale IQ was 87.4. Twenty-three (35%) children had normal language development, 13 (20%) had below average language development, and 29 (45%) had developmental language disorder. Performance IQ was significantly better than verbal IQ in all children (P < .001), and there was no difference within the 3 language groups. The performance IQ (P = .007) of children with developmental language disorder and specific language impairment was significantly lower than that of children with normal language development. Performance IQ was found to be correlated with language score (r = .309, P = .012). The children with language impairment were associated with lower IQ scores. The discrepancy between performance IQ and verbal IQ persisted in children with developmental delay, not only in children with language disorder.

Motor and language abilities from early to late toddlerhood: using formalized assessments to capture continuity and discontinuity in development

Developmental tests reflect the premise that decreases in skills over time should be a sign of atypical development. In contrast, from a psychological perspective, discontinuity may be viewed as a normal part of typical development. This study sought to describe the variability in patterns of continuity and discontinuity in developmental scores over time. Seventy-six toddlers (55% boys) from a larger screening study were evaluated at 13 and 30 months using the Mullen Scales of Early Development (MSEL) in five areas: gross motor, fine motor, visual perception, receptive language, and expressive language. Parents completed the First Year Inventory (FYI) at 12 months as well. At 30 months, 23.68% of the sample received a clinical diagnosis (e.g., developmental delay, autism spectrum disorder [ASD]). Toddlers were classified as stable, increasing, or decreasing by at least 1.5 standard deviations (SD) on their scores in each of the five MSEL areas from 13 to 30 months. Between 3.9% and 51.3% of the sample was classified as increasing and 0-23.7% as decreasing across areas. Decreases in motor areas were associated with increases in language areas. None of the toddlers showed decreases greater than 1.5 SD on their MSEL composite scores. There was no single pattern that characterized a certain diagnosis. Higher FYI sensory-regulatory risk was associated with decreases in gross motor. Lower FYI risk was linked with increases in receptive language. Developmental discontinuity in specific developmental areas was the rule rather than the exception. Interpretations of decreases in developmental levels must consider concurrent increases in skill during this emerging period.

Interactions between white matter asymmetry and language during neurodevelopment

The human brain is asymmetric in gross structure as well as functional organization. However, the developmental basis and trajectory of this asymmetry is unclear, and its relationship(s) to functional and cognitive development, especially language, remain to be fully elucidated. During infancy and early childhood, in concert with cortical gray matter growth, underlying axonal bundles become progressively myelinated. This myelination is critical for efficient and coherent interneuronal communication and, as revealed in animal studies, the degree of myelination changes in response to environment and neuronal activity. Using a novel quantitative magnetic resonance imaging method to investigate myelin content in vivo in human infants and young children, we investigated gross asymmetry of myelin in a large cohort of 108 typically developing children between 1 and 6 years of age, hypothesizing that asymmetry would predict language abilities in this cohort. While asymmetry of myelin content was evident in multiple cortical and subcortical regions, language ability was predicted only by leftward asymmetry of caudate and frontal cortex myelin content and rightward asymmetry in the extreme capsule. Importantly, the influence of this asymmetry was found to change with age, suggesting an age-specific influence of structure and myelin on language function. The relationship between language ability and asymmetry of myelin stabilized at ∼4 years, indicating anatomical evidence for a critical time during development before which environmental influence on cognition may be greatest.

Examining IQ among a clinical sample of preschool children with autism spectrum disorder over time

BACKGROUND

The cognitive functioning of children who received a diagnosis of autistic spectrum disorder (ASD) during the preschool years was assessed at the time of diagnosis (Time 1) and reassessed, on average, 3 years and 5 months later (Time 2).

METHOD

A total of 50 children were assessed (76% male, n = 38); the group had an average age of 4 years 3 months at Time 1 and 7 years 8 months at Time 2.

RESULTS

There was a significant positive relationship (r = 0.791, p < 0.01) between the group's Full Scale Intelligence Quotient (FSIQ)/Developmental Quotient (DQ) at Time 1 and at Time 2. Results indicated a significant increase in FSIQ/DQ over time for the total group and for both the High Functioning (IQ ⩾ 70) and Low Functioning (IQ < 70) groups. Of the total samples, 32% showed a clinically significant change in FSIQ/DQ of 15 points or more from Time 1 to Time 2. When age at Time 1 was included as a covariate, no significant difference was identified for change in FSIQ over time. The practical implications of the findings are discussed.

Autism in community pre-schoolers: developmental profiles

Autism is often a complex developmental disorder. The aim of the present study was to describe the developmental characteristics of 129 1-4-year-old children (102 boys, 27 girls) referred for clinical assessment (mean age 2.9 years) due to suspicion of autism spectrum disorder (ASD) after community screening at Child Health Care centers. All children were clinically assessed at the Child Neuropsychiatry Clinic (CNC) in Gothenburg by a research team (neurodevelopmental examination, structured interviews and general cognitive and language examinations). Of the 129 children, 100 met diagnostic criteria for ASD (69 with autistic disorder, and 31 with atypical autism/pervasive developmental disorder-not otherwise specified). The remaining 29 children had a variety of developmental disorders, most often attention-deficit/hyperactivity disorder (ADHD), language disorder, borderline intellectual functioning, and intellectual developmental disorder (IDD) with (n=25) or without (n=4) autistic traits (AT). IDD was found in 36% of the 100 children with ASD, and in 4% of the 25 children with AT. Of the children with ASD, 56% had language disorder with no or just a few words at the initial assessment at the CNC, many of whom in combination with IDD. Hyperactivity was found in 37% of those with ASD and in 40% of those with AT. Epilepsy was found in 6% of the total group and in 7% of those with a diagnosis of ASD. Of the latter group 11% had a history of regression, while none of the AT cases had a similar background. When results were compared with a non-screened preschool ASD group of 208 children, referred for ASD intervention at a mean age of 3.4 years, very similar developmental profiles were seen. In conclusion, early community ASD screening appears to systematically identify those children who are in need of intervention and follow-up.

Clinical outcomes of an early intervention program for preschool children with Autism Spectrum Disorder in a community group setting

Background

Available evidence indicates that early intervention programs, such as the Early Start Denver Model (ESDM), can positively affect key outcomes for children with Autism Spectrum Disorder (ASD). However, programs involving resource intensive one-to-one clinical intervention are not readily available or deliverable in the community, resulting in many children with ASD missing out on evidence-based intervention during their early and most critical preschool years. This study evaluated the effectiveness of the ESDM for preschool-aged children with ASD using a predominantly group-based intervention in a community child care setting.

Methods

Participants were 26 children (21 male) with ASD with a mean age of 49.6 months. The ESDM, a comprehensive early intervention program that integrates applied behaviour analysis with developmental and relationship-based approaches, was delivered by trained therapists during the child’s attendance at a child care centre for preschool-aged children with ASD. Children received 15–20 hours of group-based, and one hour of one-to-one, ESDM intervention per week. The average intervention period was ten months. Outcome measures were administered pre- and post-intervention, and comprised a developmental assessment - the Mullen Scales of Early Learning (MSEL); and two parent-report questionnaires - the Social Communication Questionnaire (SCQ) and Vineland Adaptive Behaviours Scales–Second Edition (VABS-II).

Results

Statistically significant post-intervention improvements were found in children’s performance on the visual reception, receptive language and expressive language domains of the MSEL in addition to their overall intellectual functioning, as assessed by standardised developmental quotients. Parents reported significant increases in their child’s receptive communication and motor skills on the VABS-II, and a significant decrease in autism-specific features on the SCQ. These effects were of around medium size, and appeared to be in excess of what may have been expected due to maturation. Nonetheless, these results need to be confirmed in a controlled study.

Conclusions

This study suggests community dissemination of the ESDM using predominantly group-based intervention may be an effective intervention. Making the ESDM accessible to the wider ASD community in child care settings has the potential for significant clinical and economic benefits. Further studies are indicated in this area, including those with younger children, and which incorporate a control group and standardised ASD assessments.

Trial registration

This trial is registered with the Australian New Zealand Clinical Trials Registry: Registry number ACTRN12612000461897.

Health-related quality of life in children and adolescents with autism spectrum disorder

OBJECTIVE

This study evaluates self- and proxy-reported health-related quality of life (HRQOL) in children and adolescents with autism spectrum disorders (ASD). The study also compares HRQOL in ASD patients with a healthy control sample and a psychiatric reference sample.

METHOD

42 children and adolescents (39 male, mean age: 12.7 ± 2.6 years, mean IQ: 100.5 ± 20.7) with the diagnosis of autism spectrum disorder (ASD) and their parents completed the Inventory for the Assessment of Quality of Life in Children and Adolescents (ILK).

RESULTS

Mean ILK LQ 0-28 scores were 20.6 (± 4.6) (self-report version) and 18.2 (± 4.0) (proxy version). Compared to a reference sample, mean ILK scores from the ASD sample were at the 47th percentile (self-report) and the 33rd percentile (proxy). Compared to children and adolescents with psychiatric disorders, self-reported ILK scores correlated with the 69th percentile, and proxy-reported ILK scores correlated with the 67th percentile. Self-reported HRQOL was significantly higher than proxy-reported HRQOL. No significant correlation was found between HRQOL and age, IQ, or autistic symptoms.

CONCLUSIONS

HRQOL in children and adolescents with ASD seems to be better than in other psychiatric disorders, but lower than in healthy controls.

Role of assessment tests in the stability of intelligence scoring of pre-school children with uneven/delayed cognitive profile

BACKGROUND

As part of an ongoing clinical service programme for pre-school children with developmental delay in an Asian developing country, we analysed the effect of three assessment tests, that is, Bayley Scale of Infant Development-II, Leiter International Performance Scale - Revised and Wechsler Preschool and Primary Scale of Intelligence - Revised - Chinese, on the stability of intelligence quotient (IQ) of children from pre-school through early childhood.

METHODS

The participants were 313 Taiwanese pre-school children with uneven or delayed cognitive profile and they were followed through early childhood. IQ stability was explored by different tests and among children of different clinical diagnosis: 168 children with non-autistic intellectual disability, 73 children with autism spectrum disorder, 58 children with mixed receptive-expressive language disorder and 14 children of other heterogeneous diagnoses. Stability of scores was evaluated using the r-squared for Pearson's coefficients to see the correlation between initial IQ (IQ1) and follow-up IQ (IQ2). Multiple linear regressions were also applied to see whether IQ1 had predictive ability for IQ2 and test-test difference in the total 313 children and each diagnostic subgroup.

RESULTS

Results revealed that mean IQ1 was 65.8 ± 15.4 while mean IQ2 was 73.2 ± 17.9 for the total 313 children. The IQs were stable across an average follow-up duration of 38.6 ± 22.1 month from pre-school into early childhood. Patterns of positive correlations between IQ1 and IQ2 were noted by all the tests (r-squared = 0.43-0.5, all P < 0.001) and in the majority of diagnostic subgroups. Multiple regressions analysis also revealed that IQ1 could predict IQ2 significantly in all the tests (all P < 0.001).

DISCUSSION

After careful choice of appropriate initial test, stability of IQ in children with developmental delay was noted from pre-school through early childhood. In addition, the translated version of cognitive assessment was valid for the required context of an Asian developing country. With the current emphasis on early identification and intervention for pre-school children with developmental delay, this information bears merit in clinical practice.

Stability and change of cognitive attributes in children with uneven/delayed cognitive development from preschool through childhood

As part of an ongoing clinical service program for children with developmental delay in an Asian developing country, we analyzed the cognitive attributes of 362 Taiwanese children (average age 48.5+/-12.9 month-old) with uneven/delayed cognitive development as they were assessed repeatedly with average duration of 39.7+/-22.6 months from preschool through early childhood. The objectives were to determine the stability and related factors in cognitive scores of these 362 children belonging to three diagnostic subgroups: 181 children with non-autistic mental retardation (MR), 95 children with autism spectrum disorder (ASD) and 64 children with mixed type developmental language disorder (DLD); and to contribute to the accumulation of data on cognitive outcome in preschool children with developmental delay. Analysis revealed that mean initial cognitive score (IQ1) was 64.9+/-16.9 while mean cognitive measure at follow-up (IQ2) was 72.2+/-19.7. Whole group analysis showed the correlation between IQ1 and IQ2 was moderate (r=0.73, p<0.001). Analysis by a general linear model showed only male gender (beta=4.95, p=0.02, C.I.=0.8-9.1) and IQ1 (beta=0.79, p<0.001, C.I.=0.68-0.90) to be significant predictors of IQ2. There were differences among three groups in IQ1 (p<0.001), IQ2 (p<0.001) and IQ change (p<0.001). Correlation coefficients of IQ1 and IQ2 were 0.6 for ASD group, 0.7 for MR group and 0.4 for DLD group respectively. The greatest proportion of children remained within the same cognitive range for both assessment points, however, it is noted that a substantial minority of children changed IQ ranges drastically from preschool through early childhood. Our results suggest that measurements of cognitive function at preschool age for children with developmental delay were valid in the context of a developing country, and the observed change in cognitive scores during follow-up emphasized the need to interpret the initial results of cognitive tests with caution.

Attention deficit/hyperactivity disorder in children and adolescents with autism spectrum disorder: symptom or syndrome?

OBJECTIVE

This study aims to evaluate ADHD-like symptoms in children with autism spectrum disorder (ASD) based on single-item analysis, as well as the comparison of two ASD subsamples of children with ADHD (ASD+) and without ADHD (ASD-).

METHODS

Participants are 83 children with ASD. Dimensional and categorical aspects of ADHD are evaluated using a diagnostic symptom checklist according to DSM-IV.

RESULTS

Of the sample, 53% fulfill DSM-IV criteria for ADHD. The comparison of the ASD+ and the ASD- samples reveals differences in age and IQ. Correlations of ADHD and PDD show significant results for symptoms of hyperactivity with impairment in communication and for inattention with stereotyped behavior. Item profiles of ADHD symptoms in the ASD+ sample are similar to those in a pure ADHD sample.

CONCLUSION

The results of our study reveal a high phenotypical overlap between ASD and ADHD. The two identified subtypes, inattentive-stereotyped and hyperactive-communication impaired, reflect the DSM classification and may theoretically be a sign of two different neurochemical pathways, a dopaminergic and a serotonergic.

Inter-rater reliability and stability of diagnoses of autism spectrum disorder in children identified through screening at a very young age

To examine the inter-rater reliability and stability of autism spectrum disorder (ASD) diagnoses made at a very early age in children identified through a screening procedure around 14 months of age. In a prospective design, preschoolers were recruited from a screening study for ASD. The inter-rater reliability of the diagnosis of ASD was measured through an independent assessment of a randomly selected subsample of 38 patients by two other psychiatrists. The diagnoses at 23 months and 42 months of 131 patients, based on the clinical assessment and the diagnostic classifications of standardised instruments, were compared to evaluate stability of the diagnosis of ASD. Inter-rater reliability on a diagnosis of ASD versus non-ASD at 23 months was 87% with a weighted kappa of 0.74 (SE 0.11). The stability of the different diagnoses in the autism spectrum was 63% for autistic disorder, 54% for pervasive developmental disorder, not otherwise specified (PDD-NOS), and 91% for the whole category of ASD. Most diagnostic changes at 42 months were within the autism spectrum from autistic disorder to PDD-NOS and were mainly due to diminished symptom severity. Children who moved outside the ASD category at 42 months made significantly larger gains in cognitive and language skills than children with a stable ASD diagnosis. In conclusion, the inter-rater reliability and stability of the diagnoses of ASD established at 23 months in this population-based sample of very young children are good.