Background and Aims:Anxiety and depression symptoms are common among autistic youth, yet little is known about the pattern and relationship of their trajectories from childhood into adolescence, a period of increasing social and academic demands. Methods:This study used parallel process latent growth curve models to examine joint trajectories, including initial levels and rate of change in caregiver-reported depression and anxiety symptoms across age 7-16 within an inception cohort of autistic youth with varied communication abilities. We also examined autistic traits, sex assigned at birth, emotional reactivity and communication ability as potential predictors. Child anxiety and depression symptoms were estimated from Child Behavior Checklist Anxiety and Affective Problems subscales, completed by caregivers approximately annually. Results:Whereas anxiety symptoms were relatively stable from childhood into adolescence, depression symptoms increased on average; significant heterogeneity of individual trajectories underlaid these overall trends. Findings indicated cross-sectional and longitudinal co-occurrence of anxiety and depression symptoms. Greater autistic traits and emotional reactivity correlated with greater initial anxiety and depression symptoms, but not their trajectories. Stronger communication ability correlated with more initial anxiety, but decreasing anxiety symptoms over time. Conclusions:Findings indicate group-level changes in depression symptoms and synchronous evolution of anxiety and depression symptoms in autistic youth across childhood and adolescence. This indicates the importance of joint monitoring of anxiety and depression symptoms in this period, with changes being potentially informative for early detection and intervention. Considering how anxiety symptom presentation may evolve across development may be a helpful next step to identifying at-risk subgroups.

Clinical guidelines recommend collecting reports from multiple informants when identifying and diagnosing challenges in children. The current study examined parent-teacher discrepancies in rating of autistic children's adaptive functioning and how these related to children's executive functions. Participants (n = 194) were a subsample of autistic children (mean age = 9.2 years; 86% male) from the Pathways in ASD cohort. We used latent profile analysis to characterise profiles based on both parent and teacher reports of adaptive functioning levels. We tested links between these profiles and indices of children's executive function and other clinical correlates. Four profiles were characterised: a lower adaptive functioning-parent higher profile, in which parents reported relatively higher scores than teachers (n = 45), an intermediate adaptive functioning profile (n = 70) and a higher adaptive functioning profile (n = 39; both characterised by similar ratings between informants) and finally, a higher adaptive functioning-teacher higher profile, in which teachers reported relatively higher scores than parents (n = 40). The higher adaptive functioning-teacher higher profile showed fewer teacher-rated executive function challenges and higher IQ compared to the other profiles. Characterising profiles facilitates interpretation of informant discrepancies and identification of clinical correlates to inform clinical decision-making.Lay abstractClinicians are advised to collect reports from multiple informants (e.g., parents and teachers), when making assessments about the wellbeing of autistic children. Parents and teachers observe children in different environments (home vs. school); therefore, collecting both reports can give a fuller account of a child's strengths and challenges. In this investigation, we looked at parent and teacher reports of autistic children's adaptive functioning, an important body of skills necessary for children to navigate daily life including practical, communication and conceptual skills. Currently, we know little about child characteristics associated with informant discrepancies, which means that it is a challenge to identify which children are most likely to display behaviour differently across contexts. We grouped n = 194 children based on the level of adaptive functioning reported by both their parent and teachers, and we compared the groups on key characteristics. We identified four groups: a lower adaptive functioning group with higher parent scores (n = 45), an intermediate group with similar scores from both informants (n = 70), a higher adaptive functioning group with similar scores from both informants (n = 39) and a higher adaptive functioning group with higher teacher scores (n = 40). Our findings indicate that many children display adaptive functioning skills differently across contexts, across levels of adaptive functioning skills. We found that children across groups differed on IQ, autistic traits and teacher-rated executive functioning. These findings can help clinicians identify and evaluate autistic children that might be likely to demonstrate different adaptive functioning skills in different environments, which could help with assessment and treatment planning.

This Response addresses methodological and conceptual issues raised in a Letter to the Editor concerning our recently published network analysis of autism characteristics and anxiety symptoms in autistic children and youth. We clarify concerns related to potential conceptual overlap between autistic characteristics and anxiety-related symptoms and address questions concerning the multinational nature of the dataset. We also summarize sensitivity and stability analyses showing that the identified bridge nodes are robust to variation in regularization parameters and operational definitions. Together, these clarifications support the interpretation of the reported network findings.

Purpose: Cross-cultural differences exist in caregiver-child engagement styles and play preferences, as well as caregivers' expectations of early intervention programs, which may necessitate modification of existing early intervention programs to suit diverse families' needs. Using the Framework for Reporting Adaptations and Modifications Expanded (FRAME) as a guide, our objective was to explore experts' opinions on necessary adaptations for early intervention programs for preschoolers with autism to be used with various cultural groups (i.e., differing ethnic, linguistic, socioeconomic, and geographic groups) other than those for which the original intervention was created. Methods: One hundred and thirteen international experts in autism intervention were contacted to participate in our surveys using the Delphi technique. Twenty participants (18 %) responded in Round 1, 21 (19 %) in Round 2, and 15 (13 %) in Round 3. Experts suggested 114 unique adaptations across FRAME elements; we added a coaching-specific category. Consensus, defined as 75 % agreement among participants, was obtained for 86 of these statements, who rated the importance of adaptations using a 4-point Likert scale. Results: Most suggestions pertained to ways in which the content of intervention should be adapted (n = 66), followed by intervention delivery (n =17), staff training (n =10), and intervention evaluation (n = 5). Sixteen coaching-specific adaptations were reported. Conclusions: Experts suggested modifications to increase families' understanding of program goals/materials, increase their comfort in participation, and to decrease attrition. These findings add to a growing body of research supporting the need for culturally responsive autism interventions.

IntroductionSleep is important for overall functioning; thus, parents should have access to effective sleep intervention for their children's insomnia. Mobile health interventions (mHealth) are increasingly popular partly due to their accessibility. Currently, no evidence-based sleep intervention apps are available for parents and their school-age children. Our research team developed the ABCs of SLEEPING intervention to address this gap.MethodThe current study used a modified version based on feedback from a feasibility study which found reasonable acceptability and promising preliminary effectiveness but lower fidelity than expected (i.e., not daily use). The current study examined preliminary effectiveness using randomized controlled trial (RCT) methodology for subjective (sleep habits, insomnia severity, behavioral functioning) and objective sleep variables, and examined recruitment data to inform practices for a future RCT. Participants were 28 parents of typically developing children with parent-reported sleep problems, randomized to a treatment or control group. Data were analyzed using descriptive statistics and analysis of covariance (ANCOVA).ResultsRecruitment rate was 70%, dropout rate was 30%, and estimated sample size for an RCT was 118. A small effect of the intervention improving sleep habits, daytime functioning, and insomnia severity, and no statistically significant effect for objectively measured sleep were demonstrated.DiscussionThese results can be used to modify the intervention and to prepare for a large-scale effectiveness study. As an accessible mHealth intervention for parents of school-aged children with insomnia, the ABCs of SLEEPING app has the potential to address an existing treatment gap.

Co-occurring autism and attention-deficit/hyperactivity disorder (ADHD) have been associated with poorer social skills. Most studies examining the association of ADHD symptoms and social skills in autism employ categorical and cross-sectional designs, which provide a narrow view of the development of ADHD symptoms. Using group-based trajectory modeling, we identified five trajectories of caregiver-reported attention problems in an inception cohort of autistic children (N = 393) followed from age 2-5 years (T1) to age 10.5-11 years (T8): Low-Stable (LS; 15.5% of participants), Low-Decreasing (LD; 25.2%), Low-Increasing (LI; 19.2%), Moderate-Decreasing (MD; 32.9%), and High-Stable (HS; 7.2%). Child FSIQ and caregiver age at baseline were lower and caregiver depression at baseline was higher for participants in the MD group than the LS group. Psychotropic medication use was associated with higher attention problems. The MD and HS groups had similar mean Vineland Adaptive Behavior Scales, Second Edition (VABS-II) Socialization standard scores at T8, which were lower than other groups. The LI group had lower Socialization scores than the LS group. Results support that a decline in caregiver-reported attention problems is common but not universal in autistic children and that even moderate/subclinical attention problems may relate to social skills outcomes in autism.

Assessing autistic traits alongside co-occurring emotional/behavioral concerns (EBCs) is challenging due to their overlap in clinical presentations, which can vary by age and sex. This study aimed to investigate domain-specific associations between autistic traits and EBCs-including anxiety, affective, attention-deficit/hyperactivity, and oppositional-defiant problems-across childhood in autistic boys and girls. We prospectively followed 389 children (84% male) diagnosed with autism at ages 2-5 years, using the Social Responsiveness Scale (SRS) and Child Behavior Checklist (CBCL) across eight timepoints until age 12. Moderated nonlinear factor analysis was used to identify and adjust for measurement non-invariance of SRS items by age, sex, and EBCs. The adjusted scores were then used for sex-moderated time-varying modeling of associations between autistic traits and EBCs. Several SRS items in the domains of social-interaction difficulties and repetitive mannerisms showed significant intercept bias by age and level of co-occurring anxiety and ADHD (effect size r > 0.20). In autistic boys, strong associations were observed between social-communication difficulties and EBCs around ages 7-9, which tended to diminish in late childhood. In contrast, autistic girls showed stable or intensifying associations, particularly with anxiety, into late childhood. Results revealed significant associations between autistic traits and EBCs after addressing item-level measurement biases. The varying associations over time highlight the importance of continuous monitoring to promptly address autistic children's sex-differential mental health needs. These findings emphasize the benefits of refining behavioral constructs and adopting a nuanced developmental approach to identify critical periods of symptom coupling/decoupling for informing evaluation and service provision.

OBJECTIVE:To determine the proportion and profile of preschoolers on the autism spectrum who do not acquire spoken language despite receiving evidence-supported interventions that target spoken language. METHODS:We examined an aggregate dataset comprising 707 preschoolers on the autism spectrum who had received evidence-supported interventions to determine the proportion and profile of those who experienced limited progress in spoken language. Interventions were delivered through programs affiliated with university research settings and ranged in duration from 6 to 24 months. Spoken language outcomes were determined from parent-report measures, which were validated against direct assessments and natural language samples. RESULTS:Approximately two-thirds of children who were non-speaking at baseline were using single words or more complex spoken language by intervention exit. Those who remained non-speaking had lower baseline motor imitation scores, derived mainly from parent reports. Approximately half of the children who were minimally speaking (i.e. had single words or no words) at baseline were combining words by intervention exit. Those who did not acquire word combinations had lower baseline scores in cognitive, social, adaptive and motor imitation measures, and shorter intervention duration. Age at intervention start influenced spoken language advancement differently depending on the initial spoken language level. The odds of acquiring spoken language did not differ based on the intervention received. CONCLUSIONS:Approximately one-third of children who had limited or no spoken language at baseline did not advance to spoken language stages following intervention. Development of spoken language was associated with modifiable factors at the child and intervention level.

OBJECTIVE:Emotional dysregulation (ED) is a common and debilitating problem for autistic children and their families. However, little is known about early-onset patterns of dysregulation, associated risk factors, and child and family outcomes. This study aimed to characterize trajectories of ED in an inception cohort of autistic preschoolers. METHOD:Caregivers reported on ED of 396 autistic children using the Aberrant Behavior Checklist Irritability and Hyperactivity/Noncompliance subscales at 6 time points from shortly after autism spectrum disorder diagnosis (ages 2-4 years) to preadolescence (ages 10-11 years). Covariance pattern mixture modeling was used to characterize the number and shape of latent dysregulation trajectories that best fit underlying data. Child and family correlates were measured at baseline and between ages 10 and 11 years to characterize early risk factors and preadolescent profiles associated with distinct latent trajectories. RESULTS:Three distinct trajectory classes best fit the data: persistently self-regulated (18% of sample), moderate and declining (54%), and persistently dysregulated (28%). Children classified in the persistently dysregulated trajectory lived with more depressed caregivers and in families reporting greater relationship problems and lower household incomes compared with children in lower-risk trajectories. Few associations were found with baseline child characteristics. Persistent dysregulation problems were associated with significantly worse child mental health and functional outcomes during preadolescent years. CONCLUSION:Risk of persistent severe ED may be identifiable at the time of early autism diagnosis. Diagnostic assessments should include contextual risk factors and links to evidence-based family supports and interventions. PLAIN LANGUAGE SUMMARY:Emotional dysregulation, in the form of frequent and severe meltdowns, irritability and impulsivity, often cause a lot of stress for children with autism spectrum disorder (ASD) and their families. Using data from the Pathways in ASD follow-up study involving 396 children diagnosed between the ages of 2 and 4 years with ASD, authors found that 28% were at high risk of severe emotional dysregulation that lasted throughout early and middle childhood. Children at highest risk were more likely to live in homes where families experienced parental depression, family relationship stress, and lower household incomes compared to those with fewer self-regulation problems. Clinicians conducting diagnostic assessments should include proactive and family-centered mental health assessments, prevention and early intervention for young children with ASD.

Examination of the effectiveness of an attention intervention using a randomized controlled trial for toddlers with suspected or confirmed autism spectrum disorder (ASD). Data was collected from Alberta, Ontario, and Nova Scotia, Canada between February 2018 and February 2020 (halted due to COVID-19 pandemic). Participants were 35 toddlers randomized to the attention condition (age at start: 25.49 + 3.91 months; 29 boys; mother's ethnicity: 65% white) and 34 toddlers randomized to a control condition. (age at start: 26.32 + 3.55 months; 24 boys; mother's ethnicity: 29% white). The results suggest that the attentional skills can be improved by a computer-based attention intervention, which in turn affects behavior observed in a real-world setting.

& centerdot; The Narrative Scoring Scheme (NSS; Heilmann et al. 2010) is a scoring grid that assesses a story's macrostructure. It has been validated for use with young neurotypically developing English monolingual children. However, it has not been validated with school-aged bilingual and monolingual children on the autism spectrum (AS), even though many of these children have dif-ficulty with macrostructure. Given the potential differences in performances between 1) younger and older children, 2) children with a neurotypical development and those on the autism spectrum, 3) between bilinguals and monolinguals, we examined the psychometric properties of the NSS with bilingual and monolingual school-aged children on the autism spectrum. Storytelling and recall tasks were completed when children were 8.5-9 (n=66) and 10.5-11 years old (n=112). Outputs were scored by trained coders using the NSS. Interrater reliability, construct validity, and internal consistency were examined. We found high interrater reliability for Total scores, adequate construct validity, and high internal consistency across ages and conditions. There were also a few differences in the NSS's psychometric properties based on bilingual/monolingual groups assignment. We can conclude that the NSS is a fairly reliable and valid tool to use with school-aged bilingual and monolingual children on the autism spectrum

BACKGROUND:Autistic children experience significantly higher rates of anxiety compared to nonautistic children. The precise relations between autism characteristics and anxiety symptoms remain unclear in this population. Previous work has explored associations at the domain level, which involve examining broad categories or clusters of symptoms, rather than the relationships between specific symptoms and/or individual characteristics. We addressed this gap by taking a network approach to understand the shared structure of autism characteristics and anxiety symptoms. METHOD:Data were pooled from five studies from Canada, Singapore, the UK, and the USA, totaling 623 autistic children (17% female sex; aged 6-18 years), for whom the parent-report Spence Children's Anxiety Scale (SCAS-P) was available. We derived two undirected regularized networks, first from the SCAS-P items only, and then by adding autism characteristics pertaining to social communication, highly focused and repetitive behavior, and sensory hypersensitivity. From these models' metrics, we extracted nodes' predictability, key bridging nodes, and community detection. RESULTS:The anxiety-only network was highly connected and consisted of four key clusters: General Anxiety, Social Anxiety, Separation Anxiety, and Panic/Agoraphobia. These broadly aligned with the existing SCAS-P structure based on DSM-IV-TR criteria. In the autism-anxiety network, the structure of anxiety remained mostly stable, with autism features forming their own community. Preference for predictability (i.e., sameness) and sensory hypersensitivity were key nodes that linked autistic features and anxiety symptoms, primarily through generalized anxiety. CONCLUSION:This study identified some of the key characteristics that bridge the broadly independent structures of autism characteristics and anxiety symptoms. The findings are discussed in the context of guiding the assessment, prevention, and treatment of anxiety in autism.

This study was conducted to determine whether school-aged autistic youth received routine vaccines at a lower rate than their non-autistic peers. In Nova Scotia (NS), Canada, vaccines routinely delivered in early adolescence are administered to Grade 7 students through a school-based Public Health vaccination program. NS youth eligible to receive Grade 7 vaccinations between 2011 and 2017 were included in this study. Autism spectrum disorder (ASD) diagnoses were determined from administrative health data. Rates of receipt of any Grade 7 vaccine and of individual vaccines were compared between autistic and non-autistic youth. Subgroup analyses included comparing Grade 7 vaccine receipt between autistic youth and their non-autistic siblings and early childhood vaccine receipt between autistic and non-autistic cohorts. The rates of receipt of any vaccine were 73

BackgroundSocial ABCs is a caregiver-mediated Naturalistic Developmental Behavioral Intervention for toddlers with confirmed/suspected Autism Spectrum Disorder (ASD), with evidence in controlled research settings. Information is lacking on implementation in community settings. We reported on the treatment effectiveness of this program within a community setting, and the current paper describes the implementation phase of this work. Distinguishing between treatment and implementation effectiveness is critical for transporting interventions from laboratory to community.ObjectivesDescribe the implementation of Social ABCs through a large public autism service, supported by a research-community partnership.MethodsWe describe this project through the Exploration, Preparation, Implementation, Sustainment (EPIS) framework as it focuses on implementation of evidence-based practices in publicly funded services. We apply this framework to the reporting stage. This project took place in the context of a 3-year government-funded pilot at a hospital-based publicly funded autism service. Participants: Program developers; Autism Service team; toddlers with suspected/confirmed ASD aged 14–34 months (M = 25.18 months) and their caregivers. Training/supervision: Provided by program developers at tapering intensity. Evaluation: Caregivers completed the Caregiver Diary and satisfaction surveys. We explored training processes, intervention uptake, acceptability, adaptations to fit community context, appropriateness, perceived impact, and facilitators/barriers.ResultsSix coaches were trained to fidelity, and three of these were further trained as Site Trainers. 183 clinically referred families enrolled and 89.4% completed the 12-week program. Caregivers reported increases in adherence and competence, high satisfaction and perceived benefits for their children. Coaches reported high satisfaction. Toddlers were appropriately identified to receive the intervention. Referral processes improved, including decreased referral age, and increased family readiness for diagnostic assessment and subsequent services.ConclusionsSocial ABCs was successfully implemented in a community service through a research-community partnership. The program was feasible, acceptable, and appropriate within a community context. Drivers of success included funding, institutional support, shared decision-making, adaptations to fit context, leadership support, perceived positive impact, and commitment to evaluation.

During the COVID-19 pandemic, the race to find an effective vaccine or treatment saw an 'extraordinary number' of clinical trials being conducted. While there were some key success stories, not all trials produced results that informed patient care. There was a significant amount of waste in clinical research during the pandemic which is said to have hampered an evidence-based response. Conducting trials which could have been predicted to fail to answer the research question (e.g. because they are not large enough to provide a definitive result) is not only a waste of resources but also a breach of research participants' trust and a violation of research ethics.The issues seen in COVID-19 clinical trials are symptomatic of a wider trial design crisis where many trials do not provide informative results. This paper examines the roles of key stakeholders in delivering ethical and informative trials and whether guidance published by 'The Good Clinical Trials Collaborative' could be used to align key stakeholder groups and enable a joined-up approach to improve clinical trial design.

Anxiety has been associated with social communication and interaction differences among autistic children. We sought to clarify the direction of these associations longitudinally, and test executive function as a moderator. Participants were autistic children (N = 157; 15% female, 85% male) engaged in a longitudinal study. Analyses focused on two timepoints during preadolescence (M ages 9.7 and 10.7 years). A cross-lagged panel model tested whether parent-reported anxiety at age 9 years predicted teacher-reported social communication and interaction differences at age 10 years, and vice versa. Next, multigroup analyses tested for similarity in cross-lagged pathways at different levels of teacher-reported metacognition and behavioural regulation (two facets of executive function). At each time point, respectively, 22% and 21% of children had anxiety exceeding a suggested clinical threshold. Longitudinal associations between parent-reported anxiety and teacher-reported social communication and interaction differences were not significant in the full sample. However, multigroup analyses found lower levels of parent-reported anxiety at age 9 years predicted greater teacher-reported social communication and interaction differences at age 10 years among participants with clinically elevated behavioural dysregulation. Findings indicate low levels of anxiety, coupled with behavioural dysregulation, may signify potential for increasing social communication and interaction differences observed by teachers among autistic children entering adolescence.Lay abstractAnxiety is a mental health concern affecting many autistic children, and has been linked to greater differences in social communication and interaction style. Executive functioning (i.e. the ability to direct and regulate attention and behaviour) plays an important role in autistic children's social-emotional development. We tested whether anxiety (reported by parents) predicts social communication and interaction differences (reported by teachers) over time or vice versa among autistic preadolescents. We also investigated whether the link between anxiety and social communication and interaction differed depending on children's EF abilities (reported by teachers). We found less parent-reported anxiety predicted more teacher-reported social communication and interaction differences a year later - but only for children who had heightened behavioural dysregulation (an aspect of executive functioning that includes impulse and emotion control). Our work suggests autistic preadolescents with behavioural dysregulation and limited anxiety may be at greater risk for social difficulties, and may need more support in this area. Executive functioning may be a useful mechanism to target in treatment for this group of children.

Abstract Background Previous research has demonstrated heterogeneous adaptive outcomes across the autism spectrum; however, the current literature remains limited in elucidating turning points and associated factors for longitudinal variability (chronogeneity). To address these empirical gaps, we aimed to provide a finer‐grained characterization of trajectories of adaptive functioning from early childhood to adolescence in autism. Methods Our sample (N = 406) was drawn from an inception cohort of children diagnosed Autistic at ages 2–5. Adaptive functioning was assessed with Vineland Adaptive Behavior Scales (VABS, 2nd Edition) across 6 visits from the time of diagnosis by age 18. Parallel‐process latent growth curve modeling were used to estimate domain‐level VABS trajectories, followed by latent class growth analysis to identify trajectory subgroups. Child characteristics at diagnosis, family demographics, and participation outcomes at adolescence were compared across subgroups. Results Piecewise latent growth models best described VABS trajectories with two turning points identified at around ages 5‐6 and 9–10, respectively reflecting transitions into school age and early adolescence. We parsed four VABS trajectory subgroups that vary by level of functioning and change rate for certain domains and periods. Around 16% of the sample exhibited overall adequate functioning (standard score >85) with notable early growth and social adaptation during adolescence. About 21% showed low adaptive functioning (standard score ≤70), with decreasing slopes by age 6 followed by improvements in communication and daily‐living skills by age 10. The other two subgroups (63% in total) were characterized by adaptive functioning between low and adequate levels, with relatively stable trajectories entering school age. These subgroups differed most in their cognitive ability at diagnosis, household income, and social participation in adolescence. Conclusions We identified key individual and family characteristics and time windows associated with distinct adaptive functioning trajectories, which have important implications for providing timely and tailored supports to Autistic people across developmental stages.

The publicly funded early intervention program for preschoolers with autism spectrum disorder (ASD) in Nova Scotia, Canada, uses the pivotal response treatment (PRT) model. Parents are coached in use of PRT strategies during their children’s first week of treatment. We explored whether parents of older preschoolers with limited verbal ability learned to implement PRT strategies with fidelity after brief coaching and whether PRT strategy use was associated with gains in children’s communication skills. We coded precoaching and postcoaching parent–child play episodes of 39 children (4.4–5.5 years) with limited verbal skills for parents’ PRT fidelity and children’s correct responding to language opportunities and frequency of initiations. Parents’ use of PRT strategies significantly improved, as did children’s responsiveness to parent-provided language opportunities. This study provides evidence for the utility of brief parent coaching in PRT for older preschoolers with ASD whose verbal skills are limited.

In the general population, irritability is associated with later depression. Despite irritability being more prevalent in autistic children, the long-term sequelae are not well explored. We tested whether irritability in early childhood predicted depression symptoms in autistic adolescents, and whether associations could be explained by difficulties in peer relationships and lower educational engagement. Analyses tested the longitudinal associations between early childhood irritability (ages 3-5) and adolescent depression symptoms (age 14) in a prospective inception cohort of autistic children (N = 390), followed from early in development shortly after they received a clinical diagnosis. Mediators were measured in mid-childhood (age 10) by a combination of measures, from which latent factors for peer relationships and educational engagement were estimated. Results showed early childhood irritability was positively associated with adolescent depression symptoms, and this association remained when adjusting for baseline depression. A significant indirect pathway through peer relationships was found, which accounted for around 13% of the association between early childhood irritability and adolescent depression, suggesting peer problems may partially mediate the association between irritability and later depression. No mediation effects were found for education engagement. Results highlight the importance of early screening and intervention for co-occurring irritability and peer problems in young autistic children.

The Autism Observation Scale for Infants (AOSI) is being applied to non infant sibling populations. Assessment of the tool’s utility across increased likelihood (IL) populations is therefore needed. A systematic review and meta-analysis was conducted on 17 studies identified from six databases. The AOSI has been used in four IL contexts: infant siblings, infants with Fragile X Syndrome, Tuberous Sclerosis Complex, and Down Syndrome. There were three main findings: (1) five studies report classification data though no consistent approach was used; (2) group differences between IL-ASD, IL non-ASD, and controls started at 12-months; and (3) large effect sizes between IL-ASD and control samples was identified. Utility of the AOSI to identify early signs of ASD in IL populations was demonstrated.