Disentangling global and domain-level adaptive behavior trajectories among children with autism spectrum disorder.

BACKGROUND: Heterogeneity in adaptive behavior abilities among people with autism spectrum disorder (ASD) is expressed not only as uneven levels of impairment across domains, but also in the developmental trajectories of adaptive skills. We studied the question of whether, after accounting for global adaptive behavior development, we find evidence of heterogeneity in the trajectories of specific domains of adaptive behavior. METHODS: A sample of 504 children with ASD was obtained by combining data from two independent natural history studies conducted in North America. We used a factor of curves model to explain growth between 36 and 138 months in Vineland Adaptive Behavior Scales, Second Edition (VABS) age equivalents as a function of domain-specific and global growth processes. RESULTS: The domain-specific trajectories in all three domains (Communication, Daily Living Skills, and Socialization) reflected impairment relative to age expectations as well as slower-than-expected growth with age, and the parameters of these trajectories were moderately-to-strongly correlated across domains. The global adaptive behavior trajectory had an initial (36-41 months of age) developmental level of about 22 age-equivalent months, and eventually slowed after initially increasing by about 6 months each year. The global trajectory accounted for the majority of variance in the domain-level processes; however, additional variance remained (14%-38%) in the domain-level intercepts, slopes, and quadratic processes. CONCLUSIONS: These results extend existing theoretical and empirical support for the hierarchical structure of adaptive behavior to include its development over time in clinical samples of children with ASD. A latent global trajectory may be sufficient to describe the growth of adaptive behavior in children with ASD; however, the remaining domain-specific variability after accounting for global adaptive behavior development allows for the possibility that differential effects of intervention on specific domains may be possible and detectable.

The membrane androgen receptor ZIP9 (SCL39A9) maintains ovarian homeostasis by mediating post-ovulatory follicle breakdown in zebrafish.

ZIP9 was recently characterized as a membrane androgen receptor in Atlantic croaker granulosa/theca (G/T) cells where it mediates androgen-induced apoptosis in vitro, but the physiological significance of this action has remained unclear. In the current study, we utilized ZIP9 knockout (zip9-/-) zebrafish to investigate the role of ZIP9-mediated androgen-induced G/T cell apoptosis in vivo. We first confirmed ZIP9 mediates apoptosis of zebrafish G/T cells in vitro. Testosterone increased apoptosis, intracellular free zinc, and expression of pro-apoptotic members bax and p53 in wildtype and zip9+/+ zebrafish G/T cells, but not in ZIP9 knockout and knockdown cell models. We hypothesized ZIP9-mediated G/T cell apoptosis may be involved in post-ovulatory follicle (POF) breakdown in vivo. Post ovulation, zip9, bax, and p53 were upregulated in zip9+/+ but not in zip9-/- ovaries. Immunoreactivity of cleaved caspase 3 was also higher in POFs from zip9+/+ ovaries compared to zip9-/-, and POF breakdown was significantly delayed in zip9-/- fish compared to zip9+/+ counterparts. To determine the detrimental consequences of delayed POF breakdown in the zip9-/- model, fish were challenged with repeated ovulation induction. After the challenge, zip9-/- fish exhibited abnormal ovarian lesions that contained debris consistent with atretic or necrotic cellular material. However, no abnormalities were observed in zip9+/+ fish ovaries, indicating that the abnormal phenotype is due to the loss of ZIP9. This study demonstrates an important role for ZIP9 in mediating POF breakdown and maintaining tissue remodeling and homeostasis in the teleost ovary and indicates a role for the ZIP9-mediated androgen-induced apoptotic response in vivo.

Longitudinal associations between early childhood irritability and adolescent depression symptoms in autistic children are mediated by peer relationships but not educational engagement.

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.

Developmental cascades between insistence on sameness behaviour and anxiety symptoms in autism spectrum disorder.

Autistic children experience high rates of anxiety. Insistence on sameness behaviour (IS) is a core feature of autism that appears correlated with anxiety severity. The objective of this study was to examine the longitudinal relations between anxiety and IS in autistic children using a developmental cascade model. A longitudinal cohort of 421 autistic children was followed between 4 and 11 years of age. Anxiety was quantified using items from the Anxiety Problems subscale of the Child Behavior Checklist; sameness behaviours were measured using the Repetitive Behavior Scale-Revised, Ritualistic/sameness subscale (both parent-report measures). Structural equation modelling was used to examine the longitudinal and directional associations between anxiety and IS at four time-points, through cross-lagged panel models (CLPM) with and without a random-intercepts component (RI-CLPM). Both the CLPM and the RI-CLPM had good fit. Significant directional associations were detected whereby elevated or increasing IS preceded elevated or increasing anxiety symptoms 1-2 years later, respectively. Stable baseline tendencies towards anxiety and IS as between-person traits (intercepts) were strongly associated (standardized estimate = 0.69, p < 0.001). The magnitude of the cross-sectional associations between anxiety and IS appeared to lessen with age. IS and anxiety symptoms in autism are closely related. They appear to be shared traits that mirror each other particularly in younger children. Increasing IS may be a sign of emerging future anxiety. Interventions that target IS to reduce or prevent anxiety amongst school-aged autistic children merit further study.

Population-Based Teacher-Rated Assessment of Anxiety Among Canadian Kindergarten Children.

Despite anxiety being a prevalent mental health problem in children, little data exist on the pervasiveness and levels of anxiety symptoms in kindergarteners. Data from the Early Development Instrument, a teacher-completed, population-level measure of child development, were collected across Canada from 2004 to 2015. The final analytic sample consisted of 974,319 children of whom 2.6% were classified as "highly anxious". Compared to children who exhibited "few to none" anxious behaviors, highly anxious children were more likely to be male, have English/French as a second language, and have a special needs designation. Furthermore, compared with their less anxious peers, highly anxious children had between 3.5 and 6.1 higher odds of scoring below the 10th percentile cut-off in physical, social, language/cognitive and communication domains. Our findings suggest that anxious behaviors are related to children's overall health and illustrate the consistency and extensiveness of anxiety at a very young age among Canadian children.

Predictors of language regression and its association with subsequent communication development in children with autism.

BACKGROUND: Language regression, broadly defined as the loss of acquired language skills in early childhood, is a distinctive feature of autism. Little is known about the factors underlying regression or the prognosis of children who exhibit regression. We examine potential predictors of language regression and test its association with language development in a prospective longitudinal sample of children with autism spectrum disorder (ASD) from diagnosis to age 10 years. METHODS: We analysed data from Pathways in ASD, a prospective longitudinal study of 421 children enrolled around the time of an autism diagnosis between 2 and 5 years. Autism Diagnostic Interview-Revised data were available for 408 children, of whom 90 (22%) were classified as having language regression. RESULTS: Demographic and other health factors including caregiver education, family income, child sex, reported seizures, and age of enrolment did not differ between children with and without language regression. Children with language regression walked earlier and attained first words sooner than those without regression. However, both groups attained phrase speech at comparable ages. Those with regression exhibited greater delays in expressive and receptive communication over the follow-up period, although this effect was attenuated when accounting for baseline differences in motor and cognitive ability. Overall, those with language regression continued to exhibit expressive but not receptive communication delay compared to those without regression. Communication trajectories were heterogeneous to age 10 years, irrespective of regression status. CONCLUSIONS: Although language regression can be alarming, our findings confirm that its occurrence does not necessarily foreshadow worse developmental outcomes relative to those without regression. Although a discrepancy in age-equivalent communication skills may persist, this can be expected to be of less practical importance with rising average levels of skills. Future studies need to account for the significant variability in language trajectories by considering factors beyond developmental regression.

Middle-childhood executive functioning mediates associations between early-childhood autism symptoms and adolescent mental health, academic and functional outcomes in autistic children.

BACKGROUND: Executive functioning (EF) varies in children with autism spectrum disorder (ASD) and is associated with clinical symptoms, academic, and adaptive functioning. Here, we examined whether middle-childhood EF mediates associations between early-childhood autism symptoms and adolescent outcomes in children with ASD. METHODS: The Pathways in ASD Cohort comprising children recruited at the time of ASD diagnosis (at 2-4 years-of-age) and followed prospectively across eight subsequent timepoints over ~10 years was used. A subset of Pathways participants (n = 250) with Behavior Rating Inventory of Executive Function (BRIEF)-Parent Form data from at least one timepoint when participants were school-aged was analyzed. A mediation framework was used to examine whether BRIEF-measured EF across age 7-10 years (middle-childhood) mediated associations between early-childhood autism symptoms (measured using the parent-report Social Responsiveness Scale across age 2-6 years) and clinical, academic, and functional outcomes, indexed at age >10-11.8 years (early-adolescence) using the Child Behavior Checklist (CBCL)-Internalizing and Externalizing Scales, Academic Performance from the Teacher's Report Form, and Vineland Adaptive Behavior Scales. Models were rerun substituting clinician-rated and teacher-rated measures, where possible. RESULTS: Mediation models indicated a significant indirect effect of middle-childhood EF on associations between early-childhood autism symptoms and externalizing behavior, academic performance, or adaptive functioning in early adolescence; kappa squared (κ2 ) effect sizes ranged from large to small. Model findings were stable across raters. Middle-childhood EF did not mediate associations between early-childhood autism symptoms and adolescent internalizing behavior. CONCLUSIONS: Among children with an ASD diagnosis, middle-childhood EF may be one pathway through which early-childhood autism symptoms influence a variety of outcomes in early-adolescence. An experimental study targeting middle-childhood EF to improve adolescent academic, emotional/behavioral, and adaptive functioning is needed to evaluate the clinical meaningfulness of these findings.

Co-occurring trajectories of anxiety and insistence on sameness behaviour in autism spectrum disorder.

BACKGROUND: Children with autism spectrum disorder (ASD) have increased susceptibility to anxiety disorders. Variation in a common ASD symptom, insistence on sameness behaviour, may predict future anxiety symptoms. AIMS: To describe the joint heterogeneous longitudinal trajectories of insistence on sameness and anxiety in children with ASD and to characterise subgroups at higher risk for anxiety. METHOD: In a longitudinal ASD cohort (n = 421), insistence on sameness behaviour was measured using the Autism Diagnostic Interview-Revised at approximately ages 3, 6 and 11 years. Anxiety was quantified at 8 time points between ages 3 and 11 years using the Child Behavior Checklist (CBCL) (parent report). Clusters of participants following similar trajectories were identified using group-based and joint trajectory modelling. RESULTS: Three insistence on sameness trajectories were identified: (a) 'low-stable' (41.7% of participants), (b) 'moderate-increasing' (52.0%) and (c) 'high-peaking' (i.e. increasing then stabilising/decreasing behaviour) (6.3%). Four anxiety trajectories were identified: (a) 'low-increasing' (51.0%), (b) 'moderate-decreasing' (16.2%), (c) 'moderate-increasing' (19.6%) and (d) 'high-stable' (13.1%). Of those assigned to the 'high-peaking' insistence on sameness trajectory, 95% jointly followed an anxiety trajectory that surpassed the threshold for clinical concern (T-score >65) by middle childhood (anxiety trajectories 3 or 4). Insistence on sameness and anxiety trajectories were similar in severity and direction for 64% of the sample; for 36%, incongruous patterns were seen (e.g. decreasing anxiety and increasing insistence on sameness). CONCLUSIONS: The concurrent assessment of insistence on sameness behaviour and anxiety in ASD may help in understanding current symptom profiles and anticipating future trajectories. High preschool insistence on sameness in particular may be associated with elevated current or future anxiety symptoms.

Coping strategies mediate the associations between COVID-19 experiences and mental health outcomes in pregnancy.

The COVID-19 pandemic has resulted in elevated mental health problems for pregnant women. Effective coping strategies likely reduce the impact of COVID-19 on mental health. This study aimed to (1) understand how COVID-19 stressors are related to different coping strategies and (2) identify whether coping strategies act as mechanisms accounting for the associations between COVID-19 stressful experiences and mental health problems in pregnancy. Participants were 304 pregnant women from Ontario, Canada. Depression, anxiety, insomnia, and perceived stress were assessed using validated measures. COVID-related stressors (i.e., financial difficulties, social isolation), subjective negative impact of COVID-19, and coping strategies used in response to COVID-19 were assessed by questionnaires. Results indicated that the subjective negative impact of COVID-19 was associated with more dysfunctional coping and less emotion-focused coping, whereas specific COVID-19 stressors, namely financial difficulties and social isolation, were associated with more dysfunctional coping and problem-focused coping. Dysfunctional coping was linked to elevated mental health problems and emotion-focused coping was linked to less mental health problems. Dysfunctional coping and emotion-focused coping partially mediated the effects of specific COVID-19 stressors on mental health outcomes. Findings indicate that coping is one pathway through which the COVID-19 pandemic impacts mental health in pregnancy. Supports and interventions for pregnant women during the pandemic should focus on bolstering coping skills, in order to minimize the mental health consequences of COVID-19.

Profiles and Predictors of Academic and Social School Functioning among Children with Autism Spectrum Disorder.

Objective: The purpose of the study was to identify profiles and predictors of academic and social functioning in a sample of school-age children with autism spectrum disorder.Method: The study included 178 children (88% boys, 75% Caucasian, ages 10-11) who completed a standardized measure of academic skills and whose teachers completed a related measure. Measures of both academic and social performance were used to construct profiles of school functioning. Measures of language, nonverbal IQ, autism symptom severity, behavior difficulties, and early social-communication skills between ages 3 and 4 were used to examine predictors of profile membership. Latent Profile Analysis was used to identify and describe profiles of children's academic and social school functioning. Profile membership was then regressed on each of the predictors using a series of multinomial logistic regression models. Finally, a multivariate model that included all significant predictors was built to examine the best fitting constellation of profile predictors.Results: Four profiles - reflecting variation in academic achievement, school engagement, socialization skills, pragmatic language use, and social relationships - captured the diverse school functioning outcomes of the sample. Profile membership was predicted by variation in imitation, responding to joint attention, language ability, nonverbal IQ and behavior difficulties between ages 3 and 4 years. However, in a multivariate model, only language and behavior difficulties emerged as significant predictors.Conclusions: A person-centered approach to targeted early intervention that reduces behavior difficulties and enhances social-communication and language abilities may prove especially important for the promotion of later academic and social functioning at school.

The application of positive parenting interventions to academic school readiness: A scoping review.

BACKGROUND: Positive parenting interventions were traditionally developed for use in infant and preschool mental health. However, there is increasing application to a broader range of developmental outcomes. A scoping review was conducted to map the landscape of the diverse applications of positive parenting interventions to academic school readiness. METHODS: Positive parenting interventions that took place in the early childhood period (prenatal to 6 years) and included an assessment of academic readiness were eligible (i.e., problem-solving/reasoning, language, executive functions and preacademics). The search strategy included four electronic databases from inception to July 2020 and backward/forward searching of the majority of eligible studies. Data charting was completed by double, independent reviewers and included theoretical frameworks, academic readiness outcomes, parenting behaviour targets, populations serviced and methodological approaches used. The synthesis included quantitative descriptives and tabular/visual representations. RESULTS: Ninety-nine studies met eligibility criteria. There has been a steady increase in published studies since 2005, with each academic readiness skill represented in varying proportions. Attachment theory was the most commonly referenced framework for applying interventions to academic readiness, with a more recent shift towards biobehavioural frameworks. The majority of studies included parental responsiveness as a parent behaviour target, whereas behavioural management was more commonly used with older children and/or those with social-emotional/behavioural difficulties. Most studies used a selective prevention approach, with low socioeconomic families being the most frequently studied group. Research gaps were identified in the measurement of follow-up and parenting behaviour. CONCLUSION: We discuss changing conceptualizations of academic readiness, applications to public health and practice, and future directions in research.

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.

Validation of the Early Development Instrument for children with special health needs.

AIM: Population-level data on the development of children with special health needs attending primary school can assist special education, health and service delivery strategies. This study aims to determine whether results of the Early Development Instrument (EDI) can be interpreted and used with the same confidence for children with special health needs as for those who are typically developing. Psychometric properties of the EDI for kindergarteners with identified special health needs are examined. METHODS: Data for children with a special health need designation come from a database of all Canadian provincial implementations of the EDI between 2004 and 2014. Item and domain characteristics (distributions of scores and measures of internal consistency) of the EDI were examined. Construct validation was assessed by correlating EDI scores with gender and age. The fit of the original factor structure of the EDI was evaluated using confirmatory factor analysis. RESULTS: Data for 29 692 children (69.8% male) were analysed. The performance of items and domains was similar to that of typically developing children. As expected, boys scored lower on all EDI domains (Cohen's d: 0.03-0.46) and a general, but non-significant, positive trend was observed between age and EDI scores. The factor structure of the EDI in this population yielded similar goodness-of-fit statistics as those reported in studies with typically developing children. CONCLUSION: Results of this investigation support the validity of the EDI in children with special health needs, paving the way for a more extensive use of EDI data for this vulnerable, yet often neglected, population.

Developmental functioning and symptom severity influence age of diagnosis in Canadian preschool children with autism.

BACKGROUND: Early diagnosis of autism spectrum disorder (ASD) is essential in most Canadian jurisdictions to access interventions that improve long-term child outcomes. Our main objective was to identify factors associated with timing of ASD diagnosis in five provinces across Canada. METHODS: Factors influencing age of diagnosis were assessed in the analyses of an inception cohort of children diagnosed with ASD between ages 2 and 5 years. We examined bivariate associations and using a series of multiple variable regression models, evaluated the unique contributions of developmental functioning, ASD symptoms and demographic variables. Children with known genetic abnormalities, or severe sensory or motor impairments interfering with assessment were excluded. RESULTS: Participants were 421 children (84.6% boys). The mean age of diagnosis was 38.2 months (SD=8.7), an average of 19 months after parents identified initial concerns. Factors associated with later diagnosis included more advanced language and cognitive skills, and higher levels of restricted repetitive behaviour symptoms. Child sex and family demographics were not associated with age of diagnosis. In regression analyses, language and cognitive skills accounted for 6.8% of variance in age of diagnosis and ASD symptoms contributed an additional 5.5%. Provincial site accounted for 4.0% of variance in age of diagnosis, independent of developmental skills and ASD symptoms. INTERPRETATION: Diagnosis of ASD occurred, on average, 19 months after parents' initial concerns. Language and cognitive skills, symptom severity and provincial site accounted for variation in age of ASD diagnosis in this Canadian cohort. Variable presentation across the developmental continuum must be considered in planning assessment services to ensure timely ASD diagnosis so that outcomes can be improved. Policy and practice leadership is also needed to reduce interprovincial variability.

Joint trajectories of internalizing and externalizing problems in preschool children with autism spectrum disorder.

The co-occurring development of internalizing and externalizing problems were examined in an inception cohort of 392 children diagnosed with autism spectrum disorder at age 3 who were assessed on four occasions. Results indicated that internalizing and externalizing problems were stable over time and highly comorbid. Joint trajectory analysis suggested that 13% of the sample followed a dual high-risk trajectory. High risk was not found to be associated with intellectual ability or autism spectrum disorder symptom severity but was linked to lower income and gender: more girls than boys were found in the high/stable internalizing problems trajectory. The results suggest that 1 in 4 preschoolers followed a trajectory of internalizing or externalizing problems (or a combination of the two) that could be characterized as clinically elevated.

Do reciprocal associations exist between social and language pathways in preschoolers with autism spectrum disorders?

BACKGROUND: Differences in how developmental pathways interact dynamically in children with autism spectrum disorder (ASD) likely contribute in important ways to phenotypic heterogeneity. This study aimed to model longitudinal reciprocal associations between social competence (SOC) and language (LANG) pathways in young children with ASD. METHODS: Data were obtained from 365 participants aged 2-4 years who had recently been diagnosed with an ASD and who were followed over three time points: baseline (time of diagnosis), 6- and 12 months later. Using structural equation modeling, a cross-lagged reciprocal effects model was developed that incorporated auto-regressive (stability) paths for SOC (using the Socialization subscale of the Vineland Adaptive Behavior Scales-2) and LANG (using the Preschool Language Scale-4 Auditory Comprehension subscale). Cross-domain associations included within-time correlations and lagged associations. RESULTS: SOC and LANG were highly stable over 12 months. Small reciprocal cross-lagged associations were found across most time points and within-time correlations decreased over time. There were no differences in strength of cross-lagged associations between SOC-LANG and LANG-SOC across time points. Few differences were found between subgroups of children with ASD with and without cognitive impairment. CONCLUSIONS: Longitudinal reciprocal cross-domain associations between social competence and language were small in this sample of young children with ASD. Instead, a pattern emerged to suggest that the two domains were strongly associated around time of diagnosis in preschoolers with ASD, and then appeared to become more independent over the ensuing 12 months.

Behavioral Pediatrics Feeding Assessment Scale in Young Children With Autism Spectrum Disorder: Psychometrics and Associations With Child and Parent Variables.

OBJECTIVE: The factor structure and validity of the Behavioral Pediatrics Feeding Assessment Scale (BPFAS; Crist & Napier-Phillips, 2001) were examined in preschoolers with autism spectrum disorder (ASD). METHODS: Confirmatory factor analysis was used to examine the original BPFAS five-factor model, the fit of each latent variable, and a rival one-factor model. None of the models was adequate, thus a categorical exploratory factor analysis (CEFA) was conducted. Correlations were used to examine relations between the BPFAS and concurrent variables of interest. RESULTS: The CEFA identified an acceptable three-factor model. Correlational analyses indicated that feeding problems were positively related to parent-reported autism symptoms, behavior problems, sleep problems, and parenting stress, but largely unrelated to performance-based indices of autism symptom severity, language, and cognitive abilities, as well as child age. CONCLUSION: These results provide evidence supporting the use of the identified BPFAS three-factor model for samples of young children with ASD.

CHAMPP4KIDS: Mixed methods study protocol to evaluate acceptability and feasibility of Parenting for Lifelong Health materials in a Canadian context.

BACKGROUND: Parents and caregivers play a key role in children's healthy development and well-being. Traditional parenting interventions promote positive parenting practices and are key to preventing child maltreatment. However, numerous barriers can limit access to programs, barriers which were further exacerbated by the COVID-19 pandemic. The Parenting for Lifelong Health group developed mass media and public health communication materials to promote positive caregiving behaviours on a population level. The Champions of Positive Parenting 4 Kids (CHAMPP4KIDS) study will examine the acceptability and feasibility of these materials for service providers and caregivers of children aged 2-6 years in Ontario, Canada. METHODS: This study will use a convergent mixed-methods design. Consenting service providers (n = 200) and caregivers (n = 100) will complete a quantitative survey to rate, rank and give feedback on Parenting for Lifelong Health tip sheets and social media ads. Caregivers will also complete self-report scales measuring depression and anxiety. We will hold focus group discussions with a sub-sample of surveyed providers (n = 40) and caregivers (n = 25). An adapted Trials of Improved Practices methodology will explore caregiver perspectives after implementing the tip sheets. Primary quantitative outcomes will be descriptive statistics of rankings, Likert Scale scores and descriptive analysis of caregiver depression and anxiety. Qualitative data will be analyzed using Rapid Qualitative Inquiry and triangulated through a convergent coding matrix. DISCUSSION: The Parenting for Lifelong Health COVID-19 parenting materials offer succinct, engaging parenting information in a mass media format that addresses some challenges associated with accessing in-person programming. The CHAMPP4KIDS study will provide mixed methods insights on the materials' acceptability and feasibility from different groups in a Canadian context, with a focus on marginalized families. The use of Trials of Improved Practices methodology could prove a useful tool for participant-led adaptation of existing parenting, early childhood development and other health intervention materials.

The Pediatric Autism Research Cohort (PARC) Study: protocol for a patient-oriented prospective study examining trajectories of functioning in children with autism.

INTRODUCTION: The developmentally variable nature of autism poses challenges in providing timely services tailored to a child's needs. Despite a recent focus on longitudinal research, priority-setting initiatives with stakeholders highlighted the importance of studying a child's day-to-day functioning and social determinants of health to inform clinical care. To address this, we are conducting a pragmatic multi-site, patient-oriented longitudinal investigation: the Pediatric Autism Research Cohort (PARC) Study. In young children (<7 years of age) newly diagnosed with autism, we will: (1) examine variability in trajectories of adaptive functioning from the point of diagnosis into transition to school; and (2) identify factors associated with trajectories of adaptive functioning. METHODS AND ANALYSIS: We aim to recruit 1300 children under 7 years of age with a recent (within 12 months) diagnosis of autism from seven sites: six in Canada; one in Israel. Participants will be followed prospectively from diagnosis to age 8 years, with assessments at 6-month intervals. Parents/caregivers will complete questionnaires administered via a customized online research portal. Following each assessment timepoint, families will receive a research summary report describing their child's progress on adaptive functioning and related domains. Analysis of the longitudinal data will map trajectories and examine child, family and service characteristics associated with chronogeneity (interindividual and intraindividual heterogeneity over time) and possible trajectory turning points around sensitive periods like the transition to school. ETHICS AND DISSEMINATION: Ethics approvals have been received by all sites. All parents/respondents will provide informed consent when enrolling in the study. Using an integrated knowledge translation approach, where stakeholders are directly engaged in the research process, the PARC Study will identify factors associated with trajectories of functioning in children with autism. Resulting evidence will be shared with government policy makers to inform provincial and national programs. Findings will be disseminated at conferences and published in peer-reviewed journals.

Investigating phenotypic heterogeneity in children with autism spectrum disorder: a factor mixture modeling approach.

BACKGROUND: Autism spectrum disorder (ASD) is characterized by notable phenotypic heterogeneity, which is often viewed as an obstacle to the study of its etiology, diagnosis, treatment, and prognosis. On the basis of empirical evidence, instead of three binary categories, the upcoming edition of the DSM 5 will use two dimensions - social communication deficits (SCD) and fixated interests and repetitive behaviors (FIRB) - for the ASD diagnostic criteria. Building on this proposed DSM 5 model, it would be useful to consider whether empirical data on the SCD and FIRB dimensions can be used within the novel methodological framework of Factor Mixture Modeling (FMM) to stratify children with ASD into more homogeneous subgroups. METHODS: The study sample consisted of 391 newly diagnosed children (mean age 38.3 months; 330 males) with ASD. To derive subgroups, data from the Autism Diagnostic Interview-Revised indexing SCD and FIRB were used in FMM; FMM allows the examination of continuous dimensions and latent classes (i.e., categories) using both factor analysis (FA) and latent class analysis (LCA) as part of a single analytic framework. RESULTS: Competing LCA, FA, and FMM models were fit to the data. On the basis of a set of goodness-of-fit criteria, a 'two-factor/three-class' factor mixture model provided the overall best fit to the data. This model describes ASD using three subgroups/classes (Class 1: 34%, Class 2: 10%, Class 3: 56% of the sample) based on differential severity gradients on the SCD and FIRB symptom dimensions. In addition to having different symptom severity levels, children from these subgroups were diagnosed at different ages and were functioning at different adaptive, language, and cognitive levels. CONCLUSIONS: Study findings suggest that the two symptom dimensions of SCD and FIRB proposed for the DSM 5 can be used in FMM to stratify children with ASD empirically into three relatively homogeneous subgroups.