Screening for autism spectrum disorders in Flemish day-care centres with the checklist for early signs of developmental disorders

Screening accuracy and cut-offs of the Polish version of Communication and Symbolic Behavior Scales-Developmental Profile Infant-Toddler Checklist

BACKGROUND

The first stage of diagnosing autism spectrum disorders usually involves population screening to detect children at risk. This study aims to assess the predictive convergent validity of the Polish version of the Communication and Symbolic Behavior Scales-Developmental Profile Infant-Toddler Checklist (CSBS-DP ITC) with the Autism Spectrum Rating Scales (ASRS), evaluate its sensitivity and specificity and assess the cut-off points for the possibility of using this questionnaire in population screening among children aged 6 to 24 months.

METHOD

The study was conducted among 602 children from the general population who had previously participated in the earlier phase of validation of the questionnaire for Polish conditions. The collected data were statistically processed to calculate the accuracy (i.e. sensitivity, specificity) of the questionnaire.

RESULTS

In individual age groups, the sensitivity of the questionnaire varies from 0.667 to 0.750, specificity from 0.854 to 0.939, positive predictive value from 0.261 to 0.4 and negative predictive value-from 0.979 to 0.981. Screening accuracy ranges from 0.847 to 0.923 depending on the age group. The adopted cut-off points are 21 points for children aged 9-12 months, 36 for children aged 13-18 months, 39 for children aged 19-24 months. Cut-off points could not be established for children aged 6-8 months. The convergent validity values with the ASRS ranged from -0.28 to -0.431 and were highest in the group of the oldest children.

CONCLUSIONS

These results indicate that the Polish version of the CSBS-DP ITC can be used as an effective tool for ASD universal screening.

Neural correlates of response to joint attention in 2-to-5-year-olds in relation to ASD and social-communicative abilities: An fNIRS and behavioral study

Autism spectrum disorder (ASD) is associated with life-long challenges with social cognition, and one of its earliest and most common manifestations is atypical joint attention, which is a pivotal skill in social-cognitive and linguistic development. Early interventions for ASD children often focus on training initiation of joint attention (IJA) and response to joint attention bids (RJA), which are important for social communication and cognition. Here, we used functional near-infrared spectroscopy and behavioral measures to test typically developing (TD, n = 17) and ASD children (n = 18), to address the relationship between the neural correlates of RJA and social-communicative behavior. Group-level differences were present for RJA-specific activation over right temporal sites, where TD children showed higher levels of activation during RJA than ASD children, whereas the two groups did not differ in the control condition. Correlations between neural activation and behavioral traits suggest that, in ASD children, neural activation during RJA is related to the frequency of RJA behavior when the former is measured over left temporal sites, and to social affect symptoms when considered for right temporal sites. Possible implications of the evidenced correlations are discussed.

Tools for early screening of autism spectrum disorders in primary health care – a scoping review

Background

Autism spectrum disorder (ASD) is a neurodevelopmental disorder that manifests itself in early childhood. Early diagnosis of these disorders allows for the initiation of early therapy, which is crucial for the child's further functioning in society.

Objectives

This review aims to gather and present the existing ASD screening tools that can be used in primary care and adapted to different countries conditions linguistically and culturally.

Eligibility criteria

We searched for English-language publications on ASD screening tools for children aged 0–3 years suitable for use in primary care (i.e. free, requiring no additional training or qualifications).

Sources of evidence

Four databases were explored to find English studies on ASD screening tools intended for the rapid assessment of children aged 0–3.

Charting methods

The information sought (specific features of the questionnaires relevant to primary health care workers, psychometric and diagnostic values of a given cultural adaptation of screening tools, and the linguistic and cultural changes made) were extracted and collected to create profiles of these tools.

Results

We found 81 studies which met inclusion criteria and underwent full data extraction. Three additional data sources were included. These allowed to create 75 profiles of adaptations for 26 different screening tools and collect data on their psychometric values and characteristic features.

Conclusions

The results of our study indicate the availability of several diagnostic tools for early ASD screening in primary care setting concordant culturally and linguistically with a given population. They could be an effective method of accelerating the diagnostic process and starting personalized therapy faster. However, most tools have significant limitations – some are only available for research purposes, while others do not have scientific evidence to prove their effectiveness.

Attitudes Towards Evidence-Based Practice of Professionals Working with Children and Adolescents with Autism Spectrum Disorder in Bangladesh

Like in many lower-middle-income countries (LMIC), progress in implementing evidence-based practices (EBPs) for children with autism spectrum disorder (ASD) has been slow in Bangladesh. This cross-sectional study examined professionals' attitudes towards evidence-based practice (EBP) for children and adolescents with ASD and explored how providers' demographic factors are related to attitudes to and adoption of EBPs in Bangladesh. The sample consisted of 150 mental health professionals and special teachers from the urban area of Dhaka. Attitudes were assessed by the Evidence-based Practice Attitude Scale-36. Findings indicated that professionals have favorable attitudes towards EBP. Their attitudes varied depending on service settings (public clinical, private clinical, and special school) and caseload per year. Professionals who work in private and special school settings claimed to be more willing to adopt an EBP when required and perceived a higher fit of EBPs and their work than those in public clinical settings. The number of different EBPs used also differed by service setting. Every type of intervention (except medication) was used by more professionals in special schools than in private and public clinical settings. Many professionals reported few barriers to the implementation of EBPs. These findings indicate conditions that are often conducive to the implementation of EBPs. However, these results do not reflect the situation in rural areas, in which poverty is more widespread and the number of specialized professionals is low.

Effectiveness of interventions for children and adolescents with autism spectrum disorder in high-income vs. lower middle-income countries: An overview of systematic reviews and research papers from LMIC

Background

There is a multitude of systematic reviews of interventions for children and adolescents with autism spectrum disorder (ASD). However, most reviews seem to be based on research conducted in High-Income Countries (HIC). Thus, summary findings may not directly apply to Lower Middle-Income Countries (LMIC). Therefore, we conducted a Meta-Review analyzing systematic reviews on the effectiveness of interventions for target outcomes in children and adolescents with ASD to find out whether there are differences in effectiveness between HIC and LMIC and which interventions can be considered evidence-based in LMIC.

Methods

Electronic databases (PsycINFO, PubMed, Cochrane database of systematic reviews) were searched for reviews on interventions for ASD in children and adolescents from January 2011 through December 2021, which included studies not coming from HIC. Systematic reviews with qualitative and quantitative syntheses of findings were included. Two investigators independently assessed studies against predetermined inclusion/exclusion criteria and extracted relevant data including quality and evidence assessments. Evidence for different types of interventions in HIC vs. LMIC was planned to be compared, but none of the reviews assessed potential differences. Therefore, a narrative review of the studies from LMIC was conducted including an assessment of quality and evidence.

Results

Thirty-five reviews fulfilled the inclusion criteria. Eleven considered findings from HIC and LMIC. Sixty-nine percent included studies with various research designs; 63% provided a qualitative synthesis of findings; 77% percent assessed the quality of studies; 43% systematically assessed the level of evidence across studies. No review compared evidence from HIC and LMIC. A review of the studies from LMIC found some promising results, but the evidence was not sufficient due to a small number of studies, sometimes poor quality, and small sample sizes.

Conclusion

Systematic reviews on interventions for children and adolescents with ASD did not look for potential differences in the effectiveness of interventions in HIC and LMIC. Overall, there is very little evidence from LMIC. None of the interventions can be considered evidence-based in LMIC. Hence, additional research and mutually agreed methodological standards are needed to provide a more secure basis for evidence-based treatments in LMIC trying to establish evidence-based practices.

Validation of the Modified Checklist for Autism in Toddlers, Revised with Follow-up in a Population Sample of 30-Month-Old Children in Iceland: A Prospective Approach

The Modified Checklist for Autism in Toddlers, Revised with Follow-up was validated on a population sample in Reykjavik, Iceland. The participants (N = 1585) were screened in well-child care at age 30 months and followed up for at least 2 years to identify autism cases. The sensitivity, specificity, positive and negative predictive values were 0.62, 0.99, 0.72, and 0.99, respectively. True-positive children were diagnosed 10 months earlier than false-negative children. Autism symptom severity and the proportions of children with verbal and performance IQs/DQs < 70 were similar between groups. Although the sensitivity was suboptimal, the screening contributed to lowering the age at diagnosis for many children. Adding autism-specific screening to the well-child care program should be considered.

Autism Screening in Early Childhood: Discriminating Autism From Other Developmental Concerns

Early identification of autism, followed by appropriate intervention, has the potential to improve outcomes for autistic individuals. Numerous screening instruments have been developed for children under 3 years of age. Level 1 screeners are used in large-scale screening to detect at-risk children in the general population; Level 2 screeners are concerned with distinguishing children with signs of autism from those with other developmental problems. The focus here is evaluation of Level 2 screeners. However, given the contributions of Level 1 screeners and the necessity to understand how they might interface with Level 2 screeners, we briefly review Level 1 screeners and consider instrument characteristics and system variables that may constrain their effectiveness. The examination of Level 2 screeners focuses on five instruments associated with published evaluations in peer-reviewed journals. Key criteria encompass the traditional indices of test integrity such as test reliability (inter-rater, test-retest) and construct validity, including concurrent and predictive validity, sensitivity (SE), and specificity (SP). These evaluations reveal limitations, including inadequate sample sizes, reliability issues, and limited involvement of independent researchers. Also lacking are comparative test evaluations under standardized conditions, hindering interpretation of differences in discriminative performance across instruments. Practical considerations constraining the use of such instruments—such as the requirements for training in test administration and test administration time—are canvassed. Published Level 2 screener short forms are reviewed and, as a consequence of that evaluation, future directions for assessing the discriminative capacity of items and measures are suggested. Suggested priorities for future research include targeting large and diverse samples to permit robust appraisals of Level 2 items and scales across the 12–36 month age range, a greater focus on precise operationalization of items and response coding to enhance reliability, ongoing exploration of potentially discriminating items at the younger end of the targeted age range, and trying to unravel the complexities of developmental trajectories in autistic infants. Finally, we emphasize the importance of understanding how screening efficacy is dependent on clinicians' and researchers' ability not only to develop screening tests but also to negotiate the complex organizational systems within which screening procedures must be implemented.

Spanish Cultural Validation of the Modified Checklist for Autism in Toddlers, Revised

The Modified Checklist for Autism in Toddlers-revised/follow-up (M-CHAT-R/F) was developed to reduce the number of cases requiring telephone verification. The aim of this study was to validate a Spanish version of the M-CHAT-R/F in the Spanish public health system. The M-CHAT-R/F was translated, culturally adapted, and then administered to 6625 children. Of the 39 positive screening cases, 15 children were diagnosed with autism spectrum disorder (ASD) and 24 with non-ASD disorders or delays. The sensitivity was 0.79 and specificity of 0.99. Positive and negative predictive values were 0.39 and 0.99, respectively. These results are similar to the English equivalent, though observed prevalence was lower. This study supports Spanish National Health System policy makers to consider a universal ASD screening program.

Autism spectrum disorder risk prediction: A systematic review of behavioral and neural investigations

A reliable diagnosis of autism spectrum disorder (ASD) is difficult to make until after toddlerhood. Detection in an earlier age enables early intervention, which is typically more effective. Recent studies of the development of brain and behavior in infants and toddlers have provided important insights in the diagnosis of autism. This extensive review focuses on published studies of predicting the diagnosis of autism during infancy and toddlerhood younger than 3 years using behavioral and neuroimaging approaches. After screening a total of 782 papers, 17 neuroimaging and 43 behavioral studies were reviewed. The features for prediction consist of behavioral measures using screening tools, observational and experimental methods, brain volumetric measures, and neural functional activation and connectivity patterns. The classification approaches include logistic regression, linear discriminant function, decision trees, support vector machine, and deep learning based methods. Prediction performance has large variance across different studies. For behavioral studies, the sensitivity varies from 20% to 100%, and specificity ranges from 48% to 100%. The accuracy rates range from 61% to 94% in neuroimaging studies. Possible factors contributing to this inconsistency may be partially due to the heterogeneity of ASD, different targeted populations (i.e., high-risk group for ASD and general population), age when the features were collected, and validation procedures. The translation to clinical practice requires extensive further research including external validation with large sample size and optimized feature selection. The use of multi-modal features, e.g., combination of neuroimaging and behavior, is worth further investigation to improve the prediction accuracy.

Systematic Review of Level 1 and Level 2 Screening Tools for Autism Spectrum Disorders in Toddlers

The present study provides a systematic review of level 1 and level 2 screening tools for the early detection of autism under 24 months of age and an evaluation of the psychometric and measurement properties of their studies. Methods: Seven databases (e.g., Scopus, EBSCOhost Research Database) were screened and experts in the autism spectrum disorders (ASD) field were questioned; Preferred Reporting Items for Systematic review and Meta-Analysis (PRISMA) guidelines and Consensus-based Standard for the selection of health Measurement INstruments (COSMIN) checklist were applied. Results: the study included 52 papers and 16 measures; most of them were questionnaires, and the Modified-CHecklist for Autism in Toddler (M-CHAT) was the most extensively tested. The measures' strengths (analytical evaluation of methodological quality according to COSMIN) and limitations (in term of Negative Predictive Value, Positive Predictive Value, sensitivity, and specificity) were described; the quality of the studies, assessed with the application of the COSMIN checklist, highlighted the necessity of further validation studies for all the measures. According to COSMIN results, the M-CHAT, First Years Inventory (FYI), and Quantitative-CHecklist for Autism in Toddler (Q-CHAT) seem to be promising measures that may be applied systematically by health professionals in the future.

Autism and family involvement in the right to education in the EU: policy mapping in the Netherlands, Belgium and Germany

Introduction

In recent years, the universal right to education has been emphasised by the Universal Declaration on Human Rights and the Convention on the Rights of Persons with Disabilities. In this paper, we mapped policies relevant to special education needs and parental involvement of children with autism at an international level and in the Netherlands, Germany and Belgium.

Methods

A policy path analysis was performed using a scoping review as an underlying methodological framework. This allowed for a rapid gathering of available data from which a timeline of adopted policies was derived.

Results and discussion

Internationally, the universal right to education has been reinforced repeatedly and the values of the Universal Declaration of Human Rights have been reiterated with every reinforcement. Also, the additional support that a child with special education needs requires is acknowledged and measures are taken to facilitate access to any education for all children. There are slight cross-country differences between the countries under study, attributable to differences in national regulation of education. However, all countries have progressed to a state where the right to education for all children is integrated on a policy level and measures are taken to enable children with special needs to participate in education. Recently, an attempt to implement a form of inclusive education was made as a form of special needs provision. Nevertheless, nowhere has this been implemented successfully yet.

Conclusion

The Universal Declaration of Human Rights was a critical juncture in international policy and created an environment where the universal right to education has been implemented for all children in the countries under study.

Identifying Atypical Development: A Role of Day-Care Workers?

Identifying the early signs of developmental disability is important for ensuring timely diagnosis and early intervention. Day-care workers may be in a prime position to notice potential developmental deviations, but it is unclear if they can accurately recognize subtle early signs of atypical development. Sixty day-care workers examined home-videos of very young children with fragile X syndrome and typically developing children. Results indicated that most day-care workers can distinguish typical and atypical development in general and might therefore have an important role in early identification. Special work experience and advanced pedagogical training appeared to boost day-care workers' sensitivity to detect atypical features in early development and to provide effective daily surveillance.

Toddler Screening for Autism Spectrum Disorder: A Meta-Analysis of Diagnostic Accuracy

Great efforts focus on early detection of autism spectrum disorder, although some scientists and policy-makers have questioned early universal screening. The aim of this meta-analysis was to evaluate the diagnostic accuracy of the different screening tools. Several electronic databases were used to identify published studies. A Bayesian model was used to estimate the screening accuracy. The pooled sensitivity was 0.72 (95% CI 0.61–0.81), and the specificity was 0.98 (95% CI 0.97–0.99). Subgroup analyses to remove heterogeneity indicated sensitivity was 0.77 (95% CI 0.69–0.84), and specificity was 0.99 (95% CI 0.97–0.99; SD ≤ 0.01). Level 1 screening tools for ASD showed consistent statistically significant results and therefore are adequate to detect autism at 14–36 months.

Building a theoretical framework for autism spectrum disorders screening instruments in Europe

BACKGROUND

This study addresses the need for a theoretical base to develop more effective early autism spectrum disorders (ASD) detection tools. The structure that underlies early ASD detection is explored by evaluating the opinions of experts on ASD screening tools currently used in Europe.

METHOD

A process of face and content validity was performed. First, the best constructs were selected from the relevant tests: Checklist for Early Signs of Developmental Disorders (CESDD), Checklist for Autism in Toddlers (CHAT), Early Screening of Autistic Traits Questionnaire (ESAT), Modified Checklist for Autism in Toddlers (M-CHAT), Social Communication Questionnaire (SCQ) and Communication and Symbolic Behaviour Scales Developmental Profile (CSBS-DP). The diagnostic content validity model by Fehring (1986, 1994) was adapted to make the selection. Afterwards, the items, taken from these tests, were selected to fit into each construct, using the same methodology.

RESULTS

Twelve of the 18 constructs were selected by the experts and 11 items were chosen from a total of 130, reduced to eight after eliminating tautologies.

CONCLUSIONS

Mapping these constructs and items on to the DSM-5 diagnostic criteria for ASD indicated good face and content validity. Results of this research will contribute to efforts to improve early ASD screening instruments and identify the key behaviours that experts in ASD see as the most relevant for early detection.

Prevalence of Autism Spectrum Disorder in a large Italian catchment area: a school-based population study within the ASDEU project

AIMS

This study aims to estimate Autism Spectrum Disorders (ASD) prevalence in school-aged children in the province of Pisa (Italy) using the strategy of the ASD in the European Union (ASDEU) project.

METHODS

A multistage approach was used to identify cases in a community sample (N = 10 138) of 7-9-year-old children attending elementary schools in Pisa - Italy. First, the number of children with a disability certificate was collected from the Local Health Authority and an ASD diagnosis was verified by the ASDEU team. Second, a Teacher Nomination form (TN) to identify children at risk for ASD was filled in by teachers who joined the study and the Social Communication Questionnaire (SCQ) was filled in by the parents of children identified as positive by the TN; a comprehensive assessment, which included the Autism Diagnostic Observation Schedule-Second Edition, was performed for children with positive TN and SCQ⩾9.

RESULTS

A total of 81 children who had a disability certificate also had ASD (prevalence: 0.79%, i.e. 1/126). Specifically, 66 children (57 males and nine females; 62% with intellectual disability -ID-) were certified with ASD, whereas another 15 (11 males and four females; 80% with ID) were recognised as having ASD among those certified with another neurodevelopmental disorder. Considering the population of 4417 (children belonging to schools which agreed to participate in the TN/SCQ procedure) and using only the number of children certified with ASD, the prevalence (38 in 4417) was 0.86%, i.e. one in 116. As far as this population is concerned, the prevalence rises to 1% if we consider the eight new cases (six males and two females; no subject had ID) identified among children with no pre-existing diagnoses and to 1.15%, i.e., one in 87, if probabilistic estimation is used.

CONCLUSIONS

This is the first population-based ASD prevalence study conducted in Italy so far and its results indicate a prevalence of ASD in children aged 7-9 years of about one in 87. This finding may help regional, national and international health planners to improve ASD policies for ASD children and their families in the public healthcare system.

A systematic review of screening tools in non-young children and adults for autism spectrum disorder

BACKGROUND

Existing reviews of screening tools for Autism Spectrum Disorder (ASD) focus on young children, and not all screening tools have been examined against validated diagnostic procedures.

AIMS

To examine the validity of screening tools for ASD in non-young children and adults to provide clinical recommendations about the use of these tools in a variety of clinical settings.

METHODS AND PROCEDURES

Electronic databases, including MEDLINE, EMBASE, PsychINFO, Cochrane Library and CINAHL, were searched through March 2017. Studies examining the validity of ASD screening tools against the Autism Diagnostic Observation Schedule and/or the Autism Diagnostic Interview - Revised in non-young children (age 4 or above) and adults were included. Three authors independently reviewed each article for data extraction and quality assessment.

OUTCOMES AND RESULTS

14 studies met the inclusion criteria, of which 11 studies were with children (4-18 years of age) and 3 studies included adults only (19 years of age and above). Included studies were conducted in a general population/low-risk sample (N = 3) and a clinically referred/high-risk sample (N = 11). In total 11 tools were included.

CONCLUSIONS AND IMPLICATIONS

Only three screening tools (the Autism-Spectrum Quotient, the Social Communication Questionnaire, and the Social Responsiveness Scale) were examined in more than 2 studies. These tools may assist in differentiating ASD from other neurodevelopmental and psychiatric disorders or typically developed children. In young adult populations, the paucity of the existing research in this group limits definitive conclusion and recommendations.

Issues in Identification and Assessment of Children with Autism and a Proposed Resource Toolkit for Speech-Language Pathologists

BACKGROUND

The prevalence of autism spectrum disorder (ASD) has increased significantly in the last decade as have treatment choices. Nonetheless, the vastly diverse autism topic includes issues related to naming, description, iden-tification, assessment, and differentiation from other neu-rodevelopmental conditions. ASD issues directly impact speech-language pathologists (SLPs) who often see these children as the second contact, after pediatric medical practitioners. Because of shared symptomology, differentiation among neurodevelopmental disorders is crucial as it impacts treatment, educational choices, and the performance trajectory of affected children.

OBJECTIVES

To highlight issues in: identification and differentiation of ASD from other communication and language challenges, the prevalence differences between ASD gender phenotypes, and the insufficient consideration of cultural factors in evaluating ASD in children. A second objective was to propose a tool to assist SLPs in the management of autism in children.

SUMMARY

A universal resource toolkit development project for SLP communities at large is proposed. The resource is comprised of research-based observation and screening tools for caregivers and educators, as well as parent questionnaires for portraying the children's function in the family, cultural com-munity, and educational setting.

Infant and dyadic assessment in early community-based screening for autism spectrum disorder with the PREAUT grid

Background

The need for early treatment of autism spectrum disorders (ASD) necessitates early screening. Very few tools have been prospectively tested with infants of less than 12 months of age. The PREAUT grid is based on dyadic assessment through interaction and shared emotion and showed good metrics for predicting ASD in very-high-risk infants with West syndrome.

Methods

We assessed the ability of the PREAUT grid to predict ASD in low-risk individuals by prospectively following and screening 12,179 infants with the PREAUT grid at four (PREAUT-4) and nine (PREAUT-9) months of age. A sample of 4,835 toddlers completed the Checklist for Autism in Toddlers (CHAT) at 24 months (CHAT-24) of age. Children who were positive at one screening (N = 100) were proposed a clinical assessment (including the Children Autism Rating Scale, a Developmental Quotient, and an ICD-10-based clinical diagnosis if appropriate) in the third year of life. A randomly selected sample of 1,100 individuals who were negative at all screenings was followed by the PMI team from three to five years of age to identify prospective false negative cases. The clinical outcome was available for 45% (N = 45) of positive children and 52.6% (N = 579) of negative children.

Results

Of the 100 children who screened positive, 45 received a diagnosis at follow-up. Among those receiving a diagnosis, 22 were healthy, 10 were diagnosed with ASD, seven with intellectual disability (ID), and six had another developmental disorder. Thus, 50% of infants positive at one screening subsequently received a neurodevelopmental diagnosis. The PREAUT grid scores were significantly associated with medium and high ASD risk status on the CHAT at 24 months (odds ratio of 12.1 (95%CI: 3.0–36.8), p < 0.001, at four months and 38.1 (95%CI: 3.65–220.3), p < 0.001, at nine months). Sensitivity (Se), specificity, negative predictive values, and positive predictive values (PPVs) for PREAUT at four or nine months, and CHAT at 24 months, were similar [PREAUT-4: Se = 16.0 to 20.6%, PPV = 25.4 to 26.3%; PREAUT-9: Se = 30.5 to 41.2%, PPV = 20.2 to 36.4%; and CHAT-24: Se = 33.9 to 41.5%, PPV = 27.3 to 25.9%]. The repeated use of the screening instruments increased the Se but not PPV estimates [PREAUT and CHAT combined: Se = 67.9 to 77.7%, PPV = 19.0 to 28.0%].

Conclusions

The PREAUT grid can contribute to very early detection of ASD and its combination with the CHAT may improve the early diagnosis of ASD and other neurodevelopmental disorders.

Early Detection and Intervention of ASD: A European Overview

Over the last several years there has been an increasing focus on early detection of Autism Spectrum Disorder (ASD), not only from the scientific field but also from professional associations and public health systems all across Europe. Not surprisingly, in order to offer better services and quality of life for both children with ASD and their families, different screening procedures and tools have been developed for early assessment and intervention. However, current evidence is needed for healthcare providers and policy makers to be able to implement specific measures and increase autism awareness in European communities. The general aim of this review is to address the latest and most relevant issues related to early detection and treatments. The specific objectives are (1) analyse the impact, describing advantages and drawbacks, of screening procedures based on standardized tests, surveillance programmes, or other observational measures; and (2) provide a European framework of early intervention programmes and practices and what has been learnt from implementing them in public or private settings. This analysis is then discussed and best practices are suggested to help professionals, health systems and policy makers to improve their local procedures or to develop new proposals for early detection and intervention programmes.

Autism Spectrum Disorder Screening Instruments for Very Young Children: A Systematic Review

Research on ASD in infancy has provided a rationale for developing screening instruments for children from the first year of life to age of 18 months. A comprehensive literature search identified candidate screening tools. Using methodological probe questions adapted from the Quality Assessment of Diagnostic Accuracy Studies (QUADAS), two Level 1 and three Level 2 screening instruments were reviewed in detail. Research evidence conclusions were that instrument development was in beginning phases, is not yet strong, and requires further development. Clinical recommendations were to continue vigilant developmental and autism surveillance from the first year on but to use the screening instruments per se only for high-risk children rather than for population screening, with considerations regarding feasibility for individual settings, informing caregivers about strengths and weaknesses of the tool, and monitoring new research.

Unraveling the nature of autism: finding order amid change

In this article, we hypothesize that individuals with autism spectrum disorder (ASD) are born with a deficit in invariance detection, which is a learning process whereby people and animals come to attend the relatively stable patterns or structural regularities in the changing stimulus array. This paper synthesizes a substantial body of research which suggests that a deficit in the domain-general perceptual learning process of invariant detection in ASD can lead to a cascade of consequences in different developmental domains. We will outline how this deficit in invariant detection can cause uncertainty, unpredictability, and a lack of control for individuals with ASD and how varying degrees of impairments in this learning process can account for the heterogeneity of the ASD phenotype. We also describe how differences in neural plasticity in ASD underlie the impairments in perceptual learning. The present account offers an alternative to prior theories and contributes to the challenge of understanding the developmental trajectories that result in the variety of autistic behaviors.

Screening for autism spectrum disorders: state of the art in Europe

A large number of studies have reported on the validity of autism spectrum disorder (ASD) screening procedures. An overall understanding of these studies' findings cannot be based solely on the level of internal validity of each, since screening instruments might perform differently according to certain factors in different settings. Europe has led the field with the development of the first screening tool and first prospective screening study of autism. This paper seeks to provide an overview of ASD screening studies and ongoing programmes across Europe, and identify variables that have influenced the outcomes of such studies. Results show that, to date, over 70,000 children have been screened in Europe using 18 different screening procedures. Differences among findings across studies have enabled us to identify ten factors that may influence screening results. Although it is impossible to draw firm conclusions as to which screening procedure is most effective, this analysis might facilitate the choice of a screening method that best fits a specific scenario, and this, in turn, may eventually improve early ASD detection procedures.

Neurobiological abnormalities in the first few years of life in individuals later diagnosed with autism spectrum disorder: a review of recent data

Background. Despite the widely-held understanding that the biological changes that lead to autism usually occur during prenatal life, there has been relatively little research into the functional development of the brain during early infancy in individuals later diagnosed with autism spectrum disorder (ASD). Objective. This review explores the studies over the last three years which have investigated differences in various brain regions in individuals with ASD or who later go on to receive a diagnosis of ASD. Methods. We used PRISMA guidelines and selected published articles reporting any neurological abnormalities in very early childhood in individuals with or later diagnosed with ASD. Results. Various brain regions are discussed including the amygdala, cerebellum, frontal cortex, and lateralised abnormalities of the temporal cortex during language processing. This review discusses studies investigating head circumference, electrophysiological markers, and interhemispheric synchronisation. All of the recent findings from the beginning of 2009 across these different aspects of defining neurological abnormalities are discussed in light of earlier findings. Conclusions. The studies across these different areas reveal the existence of atypicalities in the first year of life, well before ASD is reliably diagnosed. Cross-disciplinary approaches are essential to elucidate the pathophysiological sequence of events that lead to ASD.

Child Behavior Check List 1½-5 as a tool to identify toddlers with autism spectrum disorders: a case-control study

Tools to identify toddlers with autism in clinical settings have been recently developed. This study evaluated the sensitivity and specificity of the Child Behavior Check List 1½-5 (CBCL 1½-5) in the detection of toddlers subsequently diagnosed with an Autism Spectrum Disorder (ASD), ages 18-36 months. The CBCL of 47 children with ASD were compared to the CBCL of 47 toddlers with Other Psychiatric Disorders (OPD) as well as the CBCL of 47 toddlers with Typical Development (TD) in a case control study. One-way analysis of variance (ANOVA) and logistic regression with odds ratio (OR) analyses were performed. In order to establish the optimal threshold able to discriminate children with ASD from children with OPD and TD, Receiver Operating Characteristic (ROC) analyses were performed. One-way ANOVA revealed significant differences between the three groups. Logistic regression analysis showed that the Withdrawn and the Pervasive Developmental Problems (PDP) subscales can recognize toddlers subsequently identified as ASD from both children with TD (p<0.001) and OPD (p<0.001). ROC analyses showed very high sensitivity and specificity for the PDP (0.98 and 0.91) and Withdrawn (0.92 and 0.97) subscales when ASD was compared to TD. Sensitivity and specificity of Withdrawn (0.90 and 0.83) and PDP (0.85 and 0.83) remained high when comparing ASD versus OPD. In conclusion, the CBCL 1½-5 seemed to be able to identify toddlers subsequently diagnosed with ASD from children with TD and OPD. Its high sensitivity and specificity, coupled with its efficiency in terms of time and cost, suggest this broadband tool should be tested in a pilot screening survey of toddlers in the general population.

Measurement Issues: Screening and diagnostic instruments for autism spectrum disorders - lessons from research and practise

BACKGROUND AND SCOPE

Significant progress has been made over the past two decades in the development of screening and diagnostic instruments for autism spectrum disorders (ASDs). This article reviews this progress, including recent innovations, focussing on those instruments for which the strongest research data on validity exists, and then addresses issues arising from their use in clinical settings.

FINDINGS

Research studies have evaluated the ability of screens to prospectively identify cases of ASD in population-based and clinically referred samples, as well as the accuracy of diagnostic instruments to map onto 'gold standard' clinical best estimate diagnosis. However, extension of the findings to clinical services must be done with caution, with a full understanding that instrument properties are sample-specific. Furthermore, we are limited by the lack of a true test for ASD which remains a behaviourally defined disorder. In addition, screening and diagnostic instruments help clinicians least in the cases where they are most in want of direction, as their accuracy will always be lower for marginal cases.

CONCLUSION

Instruments help clinicians to collect detailed, structured information and increase accuracy and reliability of referral for in-depth assessment and recommendations for support, but further research is needed to refine their effective use in clinical settings.

How useful are screening instruments for toddlers to predict outcome at age 4? General development, language skills, and symptom severity in children with a false positive screen for autism spectrum disorder

Screening instruments for autism spectrum disorder (ASD) often generate many false positives. It is argued that these children may have other developmental difficulties and are also in need of thorough assessment and early intervention. The current study looked at the predictive validity of positive screens on the Checklist for Early Signs of Developmental Disorders (CESDD) and the Early Screening of Autistic Traits questionnaire (ESAT) at age 2 towards language, cognitive function, and symptom severity at age 4. Children who screened positive on the ESAT scored lower for both language and cognitive functioning at age 4 compared with children who screened negative on the ESAT. Also, the more signs of ASD that were recognized on the CESDD or ESAT, the lower the scores for language and cognitive functioning at age 4. False positive screens could be differentiated from true positive screens on the CESDD only in symptom severity score on the Autism Diagnostic Observation Schedule (ADOS). It seems that early screeners for ASD also detect children with other developmental disorders and that diagnostic instruments such as the ADOS are warranted to differentiate between children with ASD and other developmental problems.

Screening in child health: studies of the efficacy and relevance of preventive care practices

BACKGROUND

Pediatric screening enables the prevention or early detection of diseases and developmental disturbances in infancy and childhood. Screening is a standard component of pediatric practice in many countries, but its scientific basis is not well known.

METHODS

The scientific justification for pediatric screening beyond the neonatal period is presented on the basis of a selective review of the literature on some aspects of pediatric screening.

RESULTS

The level of evidence varies highly among pediatric screening interventions and can be difficult to determine because of confounding variables. Parent counseling is associated with improvements in child-raising competence, accident prevention, and reading behavior. The early detection of abnormalities in a child's motor, linguistic, mental, or social development is possible and often leads to effective early interventions. Cyanotic congenital heart defects can be detected with 63% sensitivity and 99.8% specificity; cerebral palsy can be diagnosed with 33% to 100% sensitivity and 52.3% to 100% specificity (different figures from multiple studies). Physical therapy seems to improve some manifestations of cerebral palsy. Motor development at 90 days is correlated with motor development at 57 months (72% sensitivity, 91% specificity). A developmental quotient above 85 in a two-year-old child is correlated with an intelligence quotient above 85 when the child is 7 years old.

CONCLUSION

There is an increasing amount of scientific evidence in favor of pediatric screening. Nonetheless, further epidemiological studies are needed.