Despite mounting evidence linking neurological diseases with climate change, the link between autism spectrum disorder (ASD) and global warming has yet to be explored.

To examine the relationship between the incidence of ASD and global warming from 1990 to 2019 and estimate the trajectory of ASD incidence from 2020 to 2100 globally.

We extracted meteorological data from TerraClimate between 1990 and 2019. To estimate the association between global ASD incidence and temperature variation, we adopted a two-stage analysis strategy using a generalised additive regression model. Additionally, we projected future ASD incidence under four representative shared socioeconomic pathways (SSPs: 126, 245, 370 and 585) by bootstrapping.

Between 1990 and 2019, the global mean incidence of ASD in children under 5 years old was 96.9 per 100 000. The incidence was higher in males (147.5) than in females (46.3). A 1.0 °C increase in the temperature variation was associated with a 3.0% increased risk of ASD incidence. The association was stronger in boys and children living in a low/low-middle sociodemographic index region, as well as in low-latitude areas. According to the SSP585 scenario, by 2100, the children living in regions between 10 and 20° latitude, particularly in Africa, will experience a 68.6% increase in ASD incidence if the association remains. However, the SSP126 scenario is expected to mitigate this increase, with a less than 10% increase in incidence across all latitudes.

Our study highlights the association between climate change and ASD incidence worldwide. Prospective studies are warranted to confirm the association.

3q29 deletion syndrome (3q29del) is a rare (~1:30 000) genomic disorder associated with a wide array of neurodevelopmental and psychiatric phenotypes. Prior work by our team identified clinically significant executive function (EF) deficits in 47% of individuals with 3q29del; however, the nuances of EF in this population have not been described.

We used the Behavior Rating Inventory of Executive Function (BRIEF) to perform the first in-depth assessment of real-world EF in a cohort of 32 individuals with 3q29del (62.5% male, mean age = 14.5 ± 8.3 years). All participants were also evaluated with gold-standard neuropsychiatric and cognitive assessments. High-resolution structural magnetic resonance imaging was performed on a subset of participants (n = 24).

We found global deficits in EF; individuals with 3q29del scored higher than the population mean on the BRIEF global executive composite (GEC) and all subscales. In total, 81.3% of study subjects (n = 26) scored in the clinical range on at least one BRIEF subscale. BRIEF GEC T scores were higher among 3q29del participants with a diagnosis of attention deficit/hyperactivity disorder (ADHD), and BRIEF GEC T scores were associated with schizophrenia spectrum symptoms as measured by the Structured Interview for Psychosis-Risk Syndromes. BRIEF GEC T scores were not associated with cognitive ability. The BRIEF-2 ADHD form accurately (sensitivity = 86.7%) classified individuals with 3q29del based on ADHD diagnosis status. BRIEF GEC T scores were correlated with cerebellar white matter and subregional cerebellar cortex volumes.

Together, these data expand our understanding of the phenotypic spectrum of 3q29del and identify EF as a core feature linked to both psychiatric and neuroanatomical features of the syndrome.

Scientific literature has highlighted the link between autism spectrum disorder (ASD) and anxiety disorders, but few studies have delved into the relationship between ASD and panic-agoraphobic disorders. The aim of this study is to investigate the relationship between autism spectrum and panic-agoraphobic symptoms, examining whether and which autistic domains are predictive of the presence of specific panic-agoraphobic symptoms.

Forty-five adult subjects with ASD and 50 healthy controls (HCs) were evaluated through the Structured Clinical Interview for DSM-5, Research Version and assessed with the Adult Autism Subthreshold Spectrum (AdAS Spectrum) and the Panic-Agoraphobic – Short Version (PAS-SV) questionnaires. Statistical analyses included Mann–Whitney U test, chi-square test, and a set of linear and logistic regression analyses.

The PAS-SV total and domain scores were significantly higher in the ASD group than in the HC group. A higher AdAS total score appeared to be predictive of a higher PAS-SV total score. The AdAS domain Restricted Interests and Rumination would increase the risk of obtaining higher PAS-SV total and domain scores. Conversely, the AdAS Spectrum domain Inflexibility and Adherence to Routine would predict lower total PAS-SV score.

This study revealed a greater representation of panic-agoraphobic symptoms in adults with ASD, as well as an increased risk of showing such symptoms in the presence of significant autistic traits. Restricted interests and ruminative thinking emerged as predominant risk factors for panic-agoraphobic manifestations.

Recent literature has suggested that individuals with autism spectrum disorder (ASD) or autistic traits (ATs) would be more likely to encounter traumatic events in their lifetime and to develop post-traumatic stress disorder (PTSD). However, the nature of this relationship has not yet been fully elucidated. The aims of this study were to evaluate the relationship between AT and PTSD and to investigate which specific autistic dimension was more associated with trauma and stress-related symptoms.

A total of 68 subjects with ASD and 64 healthy controls (HCs) were assessed with the Adult Autism Subthreshold Spectrum (AdAS Spectrum) and the Trauma and Loss Spectrum (TALS) questionnaires. Statistical analyses included Mann–Whitney U test, chi-square test, calculation of Spearman’s coefficients, and logistic regression analysis.

Patients with significant AT reported a 30% rate of PTSD and higher TALS total and domain scores than HCs, among whom no PTSD was found instead. Significant positive correlations were reported between AdAS Spectrum and TALS-SR scores in the whole sample. AdAS Spectrum total scores were statistically predictive of the presence of PTSD. High scores at AdAS Spectrum Inflexibility and adherence to routine and Restrictive interest and rumination domains were identified as positive predictors of a probable PTSD.

Compared to HCs, subjects with significant AT are more likely to present symptoms of PTSD. In particular, AT related to ruminative thinking, narrow interests, and sensorial reactivity would seem to predict the presence of post-traumatic stress symptomatology.

It is unclear how agenesis of the corpus callosum (ACC), a congenital brain malformation defined by complete or partial absence of the corpus callosum, impacts language development. fMRI studies of middle childhood suggest that the corpus callosum plays a role in the interhemispheric language network (Bartha-Doering et al., 2020), and that reduced interhemispheric functional connectivity is correlated with worse language abilities in children with ACC (Bartha-Doering et al., 2021). Additionally, accumulating evidence suggests structural abnormalities of the corpus callosum play a role in neurodevelopmental disorders. While children who go on to receive an autism spectrum disorder (ASD) diagnosis may show early signs of altered word and gesture acquisition (Iverson et al., 2018), the same is not known about ACC. This study examined language development during the second year of life in children with ACC in comparison to neurotypical control participants, as well as other children at elevated risk of ASD.

The MacArthur-Bates Communicative Development Inventories (MCDI): Words and Gestures scales were administered to parents of 74 children with isolated ACC at 12, 18 and 24 months of age. Children whose first language was not English and children who were bilingual were excluded. Comparison groups consisted of individuals with a low familial likelihood of ASD (LL- n=140) and individuals with high familial likelihood of ASD who do and do not have a confirmed ASD diagnosis (HL+ n=68, HL- n=256).

Compared to LL controls, the ACC group produced fewer words at 18 and 24 months of age, and demonstrated fewer words understood at all three timepoints. Similarly, compared to the HL- group, the ACC group demonstrated fewer words produced and understood at 18 months of age, and fewer words produced at 24 months of age. The ACC and HL+ groups did not differ in words produced or words understood at any timepoint.

Overall, infants with ACC demonstrated delayed vocabulary expansion from 12 to 24 months of age. These findings illustrate the role of callosal connectivity in the development of language across the first 2 years of life, and highlight the need for support and interventions that target vocabulary production and comprehension.

Childhood obesity is a serious health epidemic affecting the world today. Children who are obese earlier in life are more likely to stay obese and have an increased risk of poorer health outcomes later in life, such as diabetes and cardiovascular diseases. Obesity is also associated with deficits in executive function. Executive function (EF) is comprised of several distinct but interrelated abilities including working memory, planning, inhibition, and flexibility. Prior research suggests that obesity drives brain changes which implicate executive function structures. Our aim is to examine the relationship between childhood obesity and executive function in children with neurodevelopmental disorders.

These data are from an ongoing study on neural and behavioral phenotypes of executive functioning in children with developmental disabilities, primarily Attention-Deficit/Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD). Only study participants with complete BMI and BRIEF data were included in these analyses (n = 184). 134 representing (72.8%) of the participants were Male, 49 representing (26.6%) were Female, and 1 representing (.5%) were Gender nonconforming. 50 representing (27.2%) of the participants were between 8-9 years, 55 representing (29.9%) were between 10-11 years, and 80 representing (43.0%) were between 12-13 years. Average age was 11 years. 11 representing (6.0%) of the participants were underweight, 115 representing (62.5%) were healthy, 29 representing (15.8%) were overweight, and 29 representing (15.8%) were obese. Average BMI was 19.0, ranging from 13.2 to 36.3. 106 representing (57.6%) of the participants identified as White, 65 representing (35.3%) identified as BIPOC (2 Asian, 31 Hispanic/Latinx, 32 Black) and 13 representing (4.4%) identified as other/unspecified. 114 representing (61.9%) of the participants had a diagnosis of ADHD, ASD, or comorbid ASD and ADHD, 70 representing (38.1%) had a diagnosis of other. Average FSIQ-2 score was 106.98. Parents were asked to complete the Behavior Rating Inventory of Executive Function (BRIEF-2) and the Inhibit, Shift, Working Memory (WM), Planning, and Global Executive Composite (GEC) scales were used as the dependent measure in analyses. BMI (kg/mA2) was calculated based on CDC 2000 growth charts and classified into 4 mutually exclusive categories—underweight, healthy, overweight, and obese. There was a prediction that higher BMI would be associated with lower executive function.

A one-way ANOVA revealed a statistically significant difference between groups (F(3,180) = 3.649, p = .014). A Tukey post hoc test revealed more Shift problems in the obese group (74.55 ± 11.7) compared to the overweight group (65.79 ± 11.6, p = .026). There was no statistically significant difference between the underweight/healthy and obese groups (p = .999/p = .054). There was no statistically significant difference in mean T-scores for the Inhibit, WM, Planning, or GEC scales.

Childhood obesity and executive function deficits are significant risk factors for adult health outcomes. Obesity and elevated executive function T-scores for flexibility are related in a group of children with neurodevelopmental disorders. Future investigation will explore the role of cortical thickness and medication in these data.

This study seeks to describe the context and contents of YouTube videos featuring non-evidence-based practices (NEBPs) for autism spectrum disorder, including recent fad usage of transcranial magnetic stimulation.

A sample search of autism intervention-related YouTube videos was conducted to reflect the experience of caregivers researching autism intervention information on the internet. Exclusion criteria was applied to create a preliminary dataset. The videos were categorized into general evidence-based practice (EBP), non-evidence-based practice (NEBP), and both EBP and NEBP. The NEBP-related videos were then qualitatively described using a priori codes based on the literature regarding signs of pseudoscience, as well as an iteratively developed codebook through a constant comparative method between two independent coders.

Total videos from the YouTube search using the query "Autism Treatment" were capped at 150 videos. Total videos in English were 138. Total discrete videos (non-repeated) were 134. Total NEBP-related discrete videos were 62 (46% of final dataset); Total EBP-related videos were 38 (28.3% of final dataset); and total videos containing both EBP and NEBP as subject matter were 25 (18.6% of final dataset). Of the NEBP-related in the final dataset, the most frequent NEBP which occurred was stem cell therapy (n=26), followed by the Son-Rise program (n=13), Cannabis/marijuana (n=5), transcranial magnetic stimulation/magnetic e-resonance therapy (n=5), neurofeedback (n=1), brain rehabilitation (n=1), suramin (n=2), fecal transplants (n=2), Hyperbaric Oxygen therapy (n=1), Ayurvedic medicine (n=1), virtual reality (n=1), and others. The constant comparative method of coding yielded results specific to videos about NEBPs in autism, including: statements declaring a treatment will be effective, a banner on the YouTube page indicating if the channel is from a reputable source, a parent testimonial, a parent or caregiver display of emotion with respect to treatment efficacy, statements regarding pre-intervention repetitive or challenging behaviors, statements regarding demonstrated effects of the treatment, statements of a definitive cause of autism, statements regarding the severity of the autism in the treatment subject, specific words in reference to autism, including "disease", "toxin", or "inflammation", discussion of the financial aspect of the treatment, and videos with both high and low production values.

The likelihood of a caregiver encountering and watching videos containing NEBP-related material when using a general query to search the internet for information on autism intervention is high. Additionally, videos regarding NEBPs have more engagements (e.g., likes, comments, shares) than videos regarding EBPs, oftentimes by multitudes. The information contained within videos in which an NEBP is the subject aligns with pre-established warning signs for pseudoscience for autism interventions, however this study also contributes new warning signs through the construction of the iterative codebook. Specifically, statements about treatment efficacy in the absence of cited research, an emotional parent testimony about the individual with autism's experience with the NEBP therapy, statements regarding behavioral improvements linked to participation in the therapy oftentimes in the context of inflated claims, and clear and confident statements regarding the cause of autism with no cited research.

Concerns that exposure to more than one language in the home might negatively impact language development in young children with autism spectrum disorder (ASD) are common among caregivers. Although research directly examining the impact of a multilingual home environment in ASD is scarce, emerging evidence shows that language outcomes might be equivalent or better in children with ASD exposed to more than one language (Romero & Uddin, 2021). However, no evidence to date exists on whether exposure to more than one language affects early brain functional development in children with ASD. The current study aims to examine the (1) cross-sectional and (2) longitudinal associations between home language environment (exposure to one v. multiple languages at home, H1l vs. H>1l) and receptive and expressive language skills in young children with and without ASD, and (3) to investigate links between home language environment and brain functional network organization.

Participants included young children with ASD (n=67, mean age: 35±13 months, H>1l n=43) and typically developing (TD) children (n=39, mean age: 32±16 months, H>1l n=17) enrolled in a longitudinal study of early brain markers of autism. A subset of children with ASD for whom longitudinal behavioral data from two study visits were available (n=21, H>1l n=11) were used for exploratory analysis. Receptive language (RL) and expressive language (EL) skills were assessed by the Mullen Scales of Early Learning at each study visit. Data from 42 children with ASD (H>1l n=27) and 38 TD children (H>1l n= 15) for whom functional MRI data were acquired during natural sleep were included in functional connectivity (FC) analysis. ANCOVAs were employed to examine the effect of diagnosis, home language environment (H1l vs. H>1l) and its interaction on RL and EL skills while controlling for socioeconomic variables (i.e., maternal education level, income-to-needs ratio) and gestational age at birth. Linear mixed models were applied to explore the longitudinal effect of home language environment on RL and EL skills across two study visits in the ASD group. Lastly, FC analysis was conducted to compare functional connectivity across 7 canonical brain networks in children with and without ASD who were raised in H1l and H>1l.

We found significant diagnosis by home language environment interaction effect on EL skills, with children with ASD and H1l exhibiting the lowest EL skills. Longitudinal analysis identified a significant home language environment by study visit interaction effect on EL skills in children with ASD. Specifically, children with ASD and H1l showed lower EL skills at study visit 1 but equivalent EL skills at study visit 2 compared to children with ASD and H>1l. FC analysis revealed that children with ASD and H>1l displayed more typical brain network organization (similar to TD children) compared to those with H1l, specifically for FC between language, frontoparietal, and default mode networks.

These results suggest that early exposure to more than one language in the home may be linked with better expressive language skills in young children with ASD. Results of functional connectivity analysis also suggest that exposure to more than one language may be associated with more neurotypical functional network organization, particularly involving language and high-order networks.

Nearly 85% of adults on the autism spectrum are unemployed, although nearly 70% of those who are unemployed express a desire and willingness to work. The job interview has been identified as a significant obstacle to obtaining employment by young adults on the spectrum. A growing field of research has been focused on evaluating innovative training tools to improve interview skills. Our previous work shows that a virtual reality job interview training (VR-JIT) tool improves certain job interview skills (such as sounding professional, establishing rapport), but does not improve the ability to speak about personal strengths and abilities. The current study combined VR-JIT with a new training tool: Kessler Foundation Strength Identification and Expression (KF-STRIDE), an intervention grounded in principles of positive psychology. KF-STRIDE targets identification of personal character strengths and expressing those strengths to employers in a socially appropriate way.

The current study evaluated data from 20 autistic youth, randomized to an experimental group (n=10) and a services-as-usual (SAU) control group (n=10). Those in the experimental group participated in a 12 session intervention (9 sessions using VR-JIT and 3 sessions in KF-STRIDE). Each session was roughly one hour. Job interview performance was assessed by video-recorded mock job interviews rated by blinded assessors pre- and post- the intervention. Paired samples t-tests were conducted to examine differences in job interview skills from baseline to follow up in both groups.

The intervention group showed a significant improvement from baseline to follow-up in job interview skills in general (p = .004), and specifically sharing strengths about themselves to a future employer (p = .004). No significant differences were seen from baseline to follow-up in the SAU group. Conclusions: Individuals on the autism spectrum are significantly underemployed, which negatively impacts one’s ability to lead an independent life. Two innovative tools: VR-JIT and KF-STRIDE successfully improved job interview skills, including the ability to identify and express personal strengths. These findings indicate that these combined tools may help to improve employment skills for individuals on the autism spectrum.

Imitation has pervasive associations with social and communicative development. However, few methods have been developed to measure this construct in typically developing infants, and even less is available for at-risk populations, such as infants born preterm. Autism spectrum disorder (ASD), a particular risk of premature birth, is associated with atypical imitation and social communication. Although imitation emerges in infancy, most current screening and diagnostic tools for ASD cannot be utilized prior to 12 months. The present study aimed to develop and validate a caregiver-report measure of infant imitation, characterize imitation profiles at 4, 6, and 9 months in term and preterm infants, and explore the relationship between imitation and scores on an ASD screening questionnaire at 18 months.

Participants (N = 571) were recruited from a larger multi-site study of PediaTrac™ v3.0, a web-based tool for monitoring and tracking infant development, and were surveyed longitudinally at birth, 2, 4, 6, 9, 12, 15, and 18 months. Participants completed the online PediaTrac™ survey and several reliable and validated questionnaires via pen-and-paper format. For the purposes of this study, only the Ages and Stages Questionnaire (3rd ed.; ASQ-3), Communication and Symbolic Behavior Scales-Developmental Profile (CSBS-DP), Brief Infant Sleep Questionnaire (BISQ), and the Modified Checklist for Autism in Toddlers - Revised with Follow-Up (M-CHAT-R/F) were examined. The following hypotheses were tested: (1) proposed imitation items will represent a unitary latent construct, for which convergent and discriminant validity will be demonstrated, (2) there will be measurement invariance between term status groups at each assessment period, (3) preterm infants will obtain lower caregiver-reported imitation scores compared to term infants, and (4) imitation abilities at the assessment period with the most robust imitation factor will predict M-CHAT-R/F scores at 18 months.

Distinct imitation factors at 4, 6, and 9 months were modeled with confirmatory and exploratory factor analyses. Relationships between the factors and established measures of infant communication (CSBS; ASQ) and sleep (BISQ) revealed convergent and discriminant validity, respectively. Strict measurement invariance was demonstrated for the 4- and 9-month factors, and metric invariance for the 6-month measure. Full term infants scored higher on imitation at 9 months, though variance in this outcome was related to term status differences in sensorimotor skills. Lastly, the 9-month imitation factor, coupled with 6-month sensorimotor skills, predicted 18-month ASD risk over and above gestational age.

This study provides support for the assessment of infant imitation, utilizing imitation to detect risk in preterm infants, and extending the age of identification for ASD risk into the first year. PediaTrac™ imitation, in combination with the PediaTrac™ sensorimotor domain, may be useful in detecting developmental risk, and specifically risk for ASD, within the first year, leading to earlier initiation of intervention. Further, with its minimal completion time and ease of dissemination through digital platforms, this measure can expand access to care and improve long-term outcomes for children and families.

Delayed speech and language development is one of the main diagnostic criteria for autism spectrum disorders (ASD) and is found almost in all children with ASD. Language development in children with ASD may differ from the norm both quantitatively (delayed speech development, reduced vocabulary, scarcity of speech and limitation in its use) and qualitatively (echolalias, violation of speech grammatical structure, difficulties in the communicative use of speech). Studying different aspects of language development in ASD is very important as it provides opportunities for finer diagnostics, as well as for targeted correction of communication disorders.

The study included 34 primary-school-aged children, who were diagnosed ASD using ADOS-2, diagnostic groups included “autism” (24 children) and “autism spectrum” (8 children). Speech development was assessed using the “Korablik” test on 9 parameters: distinguishing sounds; understanding and generating nouns, verbs and syntax; text understanding; sentences repetition. Kaufman test battery (KABC-II) and the Wechsler test (WISC-III) were used to assess non-verbal intelligence. The sample was divided into two subgroups according to an educational program recommended by PMPC (Psychological, Medical and Pedagogical Commission). Group 1 included 15 children, attending program 8.1, which is recommended for children with ASD who reach developmental milestones before starting study. Group 2 included 19 children attending program 8.2, which is recommended for children with ASD who do not reach developmental milestones before starting study.

In general, all children were the best successful in understanding and generating nouns, understanding verbs, and the least successful in understanding text and searching for sound in the word. Comparing subgroups using Mann-Whitney test revealed significant differences in all measured speech parameters, except for word repetition and noun generation. Group 2 demonstrated uneven results for separate subtests - minimum scores in some subtests coexisted with maximum in others. The group also showed uneven scores distribution inside the subtests, for example, half of the children did not cope with the task to determine a sound in a word, while the rest successfully completed at least 83% of the task. A significant positive correlation between all speech subtests was found in the group. Correlation analysis for parameters of speech development, severity of autistic manifestations and non-verbal intelligence revealed a significant direct relationship between the total scores of impressive and expressive speech and IQ and an inverse relationship with the severity of autistic manifestations and disorders of social and communicative behavior. No relationships like described above were found for group 1.

Obtained results indicate variability of reasons for delayed development of various language aspects in children with ASD.

Children with congenital heart disease (CHD) have increased likelihood for Autism Spectrum Disorder (AuSD; Sigmon, Kelleman, Susi, Nylung & Oster, 2020). Even those not meeting full criteria remain at greater risk for problems with social processing/communication (Cassidy et al, 2018). The current study examined what symptoms indicative of potential AuSD were qualitatively reported by parents, and what symptoms were noted behaviorally by clinicians. These behaviors may be targets for both further clinical inquiry and intervention.

A retrospective chart review of CHD patients seen for neuropsychological assessment between the ages of 6-18 years and between 2016-2021 was conducted. The final sample included 88 patients (Ethnicity: 14% Hispanic; Race: 76% White, 17% Black/African American, 5% Asian, 1% Native American, 1% Unknown). A coding system for AuSD symptoms was derived by the authors, who are experienced in AuSD diagnosis and assessment, based on DSM-5 criteria. A comprehensive list of behaviors consistent with each symptom category was generated, and assessment reports were subsequently reviewed noting the presence, absence or “no mention” of each symptom. A second coding system was derived to assess for AuSD symptoms documented in each report’s behavioral observations. Three pediatric neuropsychologists, one post-doctoral fellow, and one psychometrist were coders, with very good reliability (k=.854 (95% CI, .827 to .881), p < .0001).

Twelve patients (14%) were diagnosed with AuSD. Age of diagnosis ranged from 3-14 years (M=7.82, SD=3.92). Main concerns parents expressed included difficulty with reciprocal conversation (75%), making friends (75%), initiating and maintaining social interactions (67%), and restrictive/intense interests (58%). During testing, providers noted variable eye contact (67%), appropriate responses to questions but minimal social conversation (67%), and exaggerated prosody (42%). Of those who did not have an AuSD diagnosis, the most frequent parent concerns included difficulty making friends (38%), difficulty initiating or maintaining social interactions (33%), atypical affect (25%), and restrictive/intense interests (18%). In this sample, providers noted concerns with answering questions but not maintaining conversation (26%), flat affect (16%), loud (17%) or soft (21%) speech volume, and socially immature behaviors (10%). Within this No Diagnosis group, general social concerns were highly correlated (point biserial) with more specific autism symptoms (e.g., intense interests, difficulty with transitions, sensory sensitivities r = .986 - .784), although most often the presence or absence of these concerns were not documented.

We examined qualitative parent-reported and provider-observed behaviors indicative of potential AuSD as detailed in a comprehensive neuropsychological evaluation report. Behaviors in children with formal AuSD diagnoses were consistent with that diagnosis, based on both parent and provider description. Of note, in children without AuSD, though, both parents and providers reported AuSD-like concerns (e.g., social communication/interaction problems, atypical interests, atypical affect, atypical speech volume) in a large minority of children. It is important that if general social concerns are present, that providers follow-up on, and document, a broader constellation of AuSD symptoms. These behaviors deserve further exploration and study within the CHD population and are important areas of inquiry in any clinical evaluation, as they should directly inform intervention.