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

The use of Language ENvironment Analysis in autism research: A systematic review

LAY ABSTRACT

In research, language ability has historically been measured using structured tasks in laboratory settings. In recent years, there has been a growing emphasis on the need to instead capture language ability in an individual's natural setting (i.e. through social interaction or in their home). Considering natural language may be particularly important for the autistic population, as an autistic child's language ability can be very different depending on the setting. One common tool for capturing natural language is the LENA recording system, which takes audio recordings over long periods of time and provides estimates of children's and caregivers' speech. The purpose of this systematic review is to summarize the use of LENA in autism research, to highlight the strengths and limitations of the system as identified by researchers, and to provide recommendations for future research and clinical use. We identified 42 autism studies that used LENA in a variety of ways and settings. Most studies used LENA within the guidelines put forth by its creators, and it was most commonly used to understand speech or speech development for autistic children. LENA is a useful tool for clinicians and caregivers to gain some insights into child speech, but those considering using it should be aware of concerns about its accuracy and limitations about the information it provides. In this review, we supplement the official LENA guidelines with specific suggestions for use with the autistic population.

Time is of the essence: Age at autism diagnosis, sex assigned at birth, and psychopathology

LAY ABSTRACT

Previous research has shown that girls/women are diagnosed later than boys/men with autism. Individuals who are diagnosed later in life, especially girls/women, have greater anxious and depressive symptoms. Previous research has been limited due to narrow inclusionary criteria for enrollment in studies. The present study uses two samples-one clinic-based, large "real-world" sample and another research-based sample with strict criteria for autism diagnosis-to understand the relationships between diagnostic age, sex assigned at birth, and symptoms of anxiety/depression. In both samples, those who were diagnosed later had greater anxious/depressive symptoms, and anxiety was not predicted by sex. In the clinic-based but not research-based sample, those assigned female at birth were diagnosed later than those assigned male at birth. In the clinic-based sample only, individuals assigned female at birth and who were later diagnosed experienced greater symptoms of anxiety/depression compared to those assigned male who benefited from earlier diagnostic timing. Within the research-based sample, those assigned female at birth had greater depressive symptoms than those assigned male. These findings highlight the importance of timely identification of autism, especially for girls/women who are often diagnosed later. Community-based samples are needed to better understand real-world sex-based and diagnostic age-based disparities in mental health.

Gender, assigned sex at birth, and gender diversity: Windows into diagnostic timing disparities in autism

LAY ABSTRACT

Later autism diagnosis is associated with risk for mental health problems. Understanding factors related to later autism diagnosis may help reduce mental health risks for autistic people. One characteristic associated with later autism diagnosis is female sex. However, studies often do not distinguish sex assigned at birth and gender identity. Gender diversity may be more common in autistic relative to neurotypical people, and autism is more common in gender-diverse populations. We studied age at autism diagnosis by sex assigned at birth, gender identity, and gender diversity (gender-diverse vs cisgender) status, separately. We studied three separate autistic samples, each of which differed in how they were diagnosed and how they were recruited. The samples included 193 persons (8.0-18.0 years) from a research-recruited academic medical center sample; 1,550 people (1.3-25.4 years) from a clinic-based sample; and 244 people (18.2-30.0 years) from a community-enriched sample. We found significant differences in the clinic-based and community-enriched samples. People assigned female sex at birth were diagnosed with autism significantly later than people assigned male at birth. People of female gender were diagnosed significantly later than people of male gender. Gender-diverse people were diagnosed significantly later than cisgender people. Sex assigned at birth, gender identity, and gender diversity may each show unique relationships with age of autism diagnosis. Differences in how autistic people are diagnosed and recruited are important to consider in studies that examine sex assigned at birth or gender identity. More research into autism diagnosis in adulthood is needed.

Delayed Milestones and Demographic Factors Relate to the Accuracy of Autism Screening in Females Using Spoken Language

Examine how milestone development, demographics, and emotional/behavioral functioning predict autistic females meeting the cutoff on a commonly used Autism screening tool (Social Communication Questionnaire: SCQ). We hypothesized that autistic girls with fewer developmental delays, whose parents have lower education, or are Black or Multiracial would be less likely to meet the SCQ cutoff. Further, those with more symptoms of Withdrawal/Depression, Social Problems, Thought Problems, and Attention Problems on the (Child Behavioral Checklist: CBCL) would be more likely to screen positive. A subset of participants enrolled in a large national cohort (SPARK) were included (5,946 autistic females). A cutoff score on the SCQ of 11 was used to form groups: Meet (M: N = 5,186) and Not Meeting (NM: N = 760). Autistic girls who had delayed toileting and motor milestones and whose parents attained higher education were more likely to screen positive. Girls who scored within the clinical range on the CBCL Thought Problems and Attention Problems syndrome scales were more likely to screen positive. Race and reported symptoms on the Withdrawn/Depressed and Social Problems syndrome scales did not relate to screening status. Results further support the existing literature suggesting that autistic girls must present with more significant delays/symptoms to be screened and diagnosed with autism, which can could impact their access to early intervention services and future skill development. Future research should examine additional factors that specifically put females at a disadvantage for being accurately identified, particularly for those who are speaking and/or of average cognitive ability.

Autism Prevalence and the Intersectionality of Assigned Sex at Birth, Race, and Ethnicity on Age of Diagnosis

PURPOSE

An official autism diagnosis is required to access timely intervention and is associated with better long-term wellbeing and mental health. Certain demographic characteristics, such as being female or a racially or ethnically minoritized youth, have been associated with significant diagnostic lag. However, it remains unclear how assigned sex, race, and ethnicity interact with each other in predicting the prevalence and age of autism diagnosis.

METHODS

To examine the interactions between assigned sex, race, and ethnicity, we used data from the National Survey of Children's Health (NSCH; 2016 > 2021).

RESULTS

One in 38 children had an autism diagnosis and 3.8 males were diagnosed per 1 female. Hierarchical linear regressions yielded diagnostic delays in some females, particularly those who were non-Hispanic white, Black, and Asian. Ethnic and racial minority children had significantly earlier diagnoses than white and non-Hispanic children when not accounting for sex.

CONCLUSION

This study demonstrates slight increases in reported autism prevalence, a diagnostic lag in some autistic females that was strongly associated with ethnicity, and earlier diagnoses in racial and ethnic minority youth, a finding that may be explained by factors associated with phenotypic differences. This study has important implications for the diagnosis of minority autistic youth, particularly females and females who are non-Hispanic, who may experience a greater propensity for diagnostic delays.

Are the diagnostic rates of autistic females increasing? An examination of state-wide trends

BACKGROUND

Autism has been considered a 'male-dominant' condition. However, recent research suggests that autistic females are underdiagnosed, misdiagnosed, and later diagnosed. Females may also have different and more nuanced behavioral profiles. To examine diagnosis rates of females, we used 20 years of state-wide data to characterize historical trends in the diagnosis of autism in females to determine whether the proportion of females diagnosed with autism has changed over time.

METHODS

Data were drawn from 10,247 participants (males = 8,319, females = 1928) who received an autism diagnosis between 2000 and 2021 from state-wide autism centers associated with the University of North Carolina TEACCH Autism Program.

RESULTS

The rates of females diagnosed with autism increased at a greater rate compared with males. Age of diagnosis remained consistently higher for females. Late diagnosis (defined as 13+) increased over time across both males and females, however, was more commonly associated with females, particularly those with co-occurring intellectual disability.

CONCLUSIONS

Our results indicate that the proportion of females diagnosed with autism has increased steadily over a 20-year period, which likely reflects greater societal knowledge of how autism may manifest differentially in females.

Potential mechanisms underlying the association between feeding and eating disorders and autism

There is a reliable association between autism and Feeding and Eating Disorders. Concerningly, where these two conditions co-occur, clinical outcomes of Feeding and Eating Disorders are significantly worse, and treatment less effective, than when the Feeding and Eating Disorders occur in neurotypical individuals. Problematically, the reason for the association between autism and Feeding and Eating Disorders is poorly understood, which constrains advances in clinical care. This paper outlines several possible mechanisms that may underlie the observed association and suggests ways in which they may be empirically tested. Mechanisms are split into those producing an artefactual association, and those reflecting a genuine link between conditions. Artefactual associations may be due to conceptual overlap in both diagnostic criteria and measurement, Feeding and Eating Disorders causing transient autistic traits, or the association being non-specific in nature. A genuine association between autism and Feeding and Eating Disorders may be due to common causal factors, autism directly or indirectly causing Feeding and Eating Disorders, and Feeding and Eating Disorders being a female manifestation of autism.

Sex differences during development in cortical temporal processing and event related potentials in wild-type and fragile X syndrome model mice

BACKGROUND

Autism spectrum disorder (ASD) is currently diagnosed in approximately 1 in 44 children in the United States, based on a wide array of symptoms, including sensory dysfunction and abnormal language development. Boys are diagnosed ~ 3.8 times more frequently than girls. Auditory temporal processing is crucial for speech recognition and language development. Abnormal development of temporal processing may account for ASD language impairments. Sex differences in the development of temporal processing may underlie the differences in language outcomes in male and female children with ASD. To understand mechanisms of potential sex differences in temporal processing requires a preclinical model. However, there are no studies that have addressed sex differences in temporal processing across development in any animal model of ASD.

METHODS

To fill this major gap, we compared the development of auditory temporal processing in male and female wildtype (WT) and Fmr1 knock-out (KO) mice, a model of Fragile X Syndrome (FXS), a leading genetic cause of ASD-associated behaviors. Using epidural screw electrodes, we recorded auditory event related potentials (ERP) and auditory temporal processing with a gap-in-noise auditory steady state response (ASSR) paradigm at young (postnatal (p)21 and p30) and adult (p60) ages from both auditory and frontal cortices of awake, freely moving mice.

RESULTS

The results show that ERP amplitudes were enhanced in both sexes of Fmr1 KO mice across development compared to WT counterparts, with greater enhancement in adult female than adult male KO mice. Gap-ASSR deficits were seen in the frontal, but not auditory, cortex in early development (p21) in female KO mice. Unlike male KO mice, female KO mice show WT-like temporal processing at p30. There were no temporal processing deficits in the adult mice of both sexes.

CONCLUSIONS

These results show a sex difference in the developmental trajectories of temporal processing and hypersensitive responses in Fmr1 KO mice. Male KO mice show slower maturation of temporal processing than females. Female KO mice show stronger hypersensitive responses than males later in development. The differences in maturation rates of temporal processing and hypersensitive responses during various critical periods of development may lead to sex differences in language function, arousal and anxiety in FXS.

Altered Developmental Trajectory in Male and Female Rats in a Prenatal Valproic Acid Exposure Model of Autism Spectrum Disorder

Early motor and sensory developmental delays precede Autism Spectrum Disorder (ASD) diagnosis and may serve as early indicators of ASD. The literature on sensorimotor development in animal models is sparse, male centered, and has mixed findings. We characterized early development in a prenatal valproic acid (VPA) model of ASD and found sex-specific developmental delays in VPA rats. We created a developmental composite score combining 15 test readouts, yielding a reliable gestalt measure spanning physical, sensory, and motor development, that effectively discriminated between VPA and control groups. Considering the heterogeneity in ASD phenotype, the developmental composite offers a robust metric that can enable comparison across different animal models of ASD and can serve as an outcome measure for early intervention studies.

Improving early detection, diagnosis and intervention for children with autism spectrum disorder: A cross-sectional survey in China

BACKGROUND

Detection and diagnosis of autism spectrum disorder (ASD) are prerequisites for early interventions. However, few studies focused on this topic.

AIM

This study aims to characterize the timing from symptom detection to intervention in children with ASD and identify predictors of age at ASD diagnosis, presence of intervention, and the time lag between detection and diagnosis.

METHODS AND PROCEDURES

A cross-sectional survey was conducted with 303 parents (111 fathers and 192 mothers, 21-54 years) of children with ASD in Guangzhou, China.

OUTCOMES AND RESULTS

The median time from symptom observation to the first doctor visit was 3 months, while the time to ASD diagnosis averaged 6 months. Most children (76.24 %) were diagnosed within one year after detection, and 25.58 % had no intervention after diagnosis. Predictors of earlier ASD diagnosis included ASD-related symptoms identified at an older age, less serious symptoms, and initial symptoms with atypical motor development and sensory anomalies. ASD-related symptoms observed at an older age, initial symptoms with social deficits, sensory anomalies, and without language impairment, primary caregivers other than parents, families with lower income, and less social support utilization increased the odds of a time lag between detection and diagnosis. Children with fathers having lower education were less likely to receive interventions.

CONCLUSIONS AND IMPLICATIONS

Earlier ASD identification and intervention might be facilitated by health education on typical symptoms of ASD for parents with young children and incorporating ASD screening during routine health examinations for children. For children whose primary caregivers are not their parents and from lower-income families, additional support may be required for timely diagnosis after reporting ASD-related symptoms. Moreover, more intervention supports are expected for children whose fathers have lower education levels. Helping families take full advantage of support is also important for early diagnosis and intervention.

Intersecting effects of sex/gender and autism on structural language: A scoping review

LAY ABSTRACT

Research about autism is mostly about boys and men, even though many autistic people are girls, women, and transgender/nonbinary. We wanted to learn more about how gender interacts with language skills in autistic people, so we reviewed existing research articles on this topic. We also wanted to know how this previous research talked about gender. Included articles had to measure language skills for autistic people of different genders. They also had to be published between 2000 and 2021. Twenty-four articles met these requirements. We found that autistic girls showed better language skills than autistic boys but worse skills than nonautistic girls. This may be one reason that autistic girls are underdiagnosed compared to autistic boys. If we compare autistic girls to nonautistic girls instead, we can see more language differences and possible areas to target in interventions. This study supports the need to create diagnostic and support measures for autism that take gender into account. Also, only one article mentioned autistic people who are transgender or nonbinary. Researchers who want to learn more about gender and autism need to understand gender diversity and recognize that many autistic people are transgender or nonbinary.

Association Between Early Developmental Milestones and Autism Spectrum Disorder

Early diagnosis and treatment of autism spectrum disorder (ASD) has been shown to lead to better prognosis. Here, we examined the association of commonly measured early developmental milestones (DMs) with later diagnosis of ASD. We conducted a case-control study of 280 children with ASD (cases) and 560 typically developed children (controls) matched to cases by date of birth, sex, and ethnicity in a control/case ratio of 2:1. Both cases and controls were ascertained from all children whose development was monitored at mother-child health clinics (MCHCs) in southern Israel. DM failure rates during the first 18 months of life in three developmental categories (motor, social, and verbal) were compared between cases and controls. Conditional logistic regression models were used to assess the independent association of specific DMs with the risk of ASD, while adjusting for demographic and birth characteristics.Significant case-control differences in DM failure rates were observed as early as 3 months of age (p < 0.001), and these differences increased with age. Specifically, cases were 2.4 times more likely to fail ≥ 1 DM at 3 months (aOR = 2.39; 95%CI = 1.41-4.06), and 15.3 times more likely to fail ≥ 3 DMs at 18 months (aOR = 15.32; 95%CI = 7.75-30.28). The most notable DM-ASD association was observed for social DM failure at 9-12 months (aOR = 4.59; 95%CI = 2.59-8.13). Importantly, the sex or ethnicity of the participants did not affect these DM-ASD associations. Our findings highlight the potential role of DMs as early signs of ASD that could facilitate earlier referral and diagnosis of ASD.

Common Intersection of Autism and Gender Diversity in Youth: Clinical Perspectives and Practices

Autism and gender diversity often intersect. Many transgender youth seeking gender-related medical interventions are autistic. Clinicians serving these youth lack an autism-specific evidence base to guide gender care decisions. At present, care decisions are based on extrapolation of care models from transgender youth samples, generally. At this point, there is no evidence to suggest that autistic youth are likely to experience shifts in gender or gender-related medical requests, although this has been insufficiently studied. In this article, cowritten by expert clinicians and autistic gender-diverse collaborators, an overview of clinical care considerations and the current evidence base is provided.

Sex/Gender Differences in the Language Profiles of Italian Children with Autism Spectrum Disorder: A Retrospective Study

Sex/gender (S/G) differences in ASD language profiles have been poorly investigated. The present study aims to explore whether male (M) and female (F) children with ASD and with normal non-verbal cognitive abilities differ in their linguistic profiles. A sample of 76 Italian children with ASD (range: 4.9-8 years), including 50 Ms and 26 Fs, was retrospectively recruited. Language profiles were analyzed using standardized tests for the evaluation of receptive and expressive vocabulary as well as grammar. Grammatical comprehension was the most impaired domain compared to the other language measures in both M and F children. Comparing language profiles between S/G, Fs showed significantly better scores than Ms in grammatical production (p = 0.002), and Ms showed better active negative sentence comprehension (p = 0.035). Moreover, comparing the language profiles between Ms and Fs with a receptive disorder, Fs had significantly worse grammatical comprehension and better grammatical production than Ms. Even among children without a receptive disorder, Fs had significantly higher grammatical production scores. The S/G differences in language profile, particularly better expressive language in Fs than Ms, can partially contribute to the delayed ASD diagnosis or underdiagnosis of Fs without intellectual disability. Finally, the results document the importance of accurately investigating both expressive and receptive abilities in children with ASD.

Sex differences in neurodevelopmental trajectories in children with different levels of autistic traits

AIM

Little is known about early manifestations of autism spectrum disorders (ASD) in females, including those who may be overlooked by the current diagnostic criteria. We longitudinally explored sex differences in the trajectories of cognitive and motor functions and adaptive behaviors in children with different levels of autistic traits.

METHODS

The participants were 824 children from the Hamamatsu Birth Cohort for Mothers and Children (HBC Study), Japan, who were classified into three autistic trait groups-low, moderate, and high-based on the Social Responsiveness Scale-Second Edition. Cognitive and motor functions were measured at seven time-points from 0.5 to 3.5 years of age using the Mullen Scales of Early Learning. Adaptive behaviors were measured at five time-points from 2.7 to 9 years of age using the Vineland Adaptive Behavior Scales-Second Edition. Trajectories were depicted using latent growth curve modeling.

RESULTS

Sex-specific trajectories were observed in the high-autistic-trait group, with only males showing a temporary decline in expressive language around the age of 2 years and a slight improvement thereafter. They also showed a slight improvement around 3 years in the adaptive behavior communication domain but a gradual downward trend later. Females in the high-autistic-trait group showed no distinct manifestation before the age of 3 years but showed a downward trend after 3.5 years in the adaptive behavior communication domain.

CONCLUSION

Females and males with higher autistic traits than their same-sex peers, independent of clinical diagnosis, may have different phenotypes in certain neurodevelopmental domains during infancy and early childhood.

Sex Differences in Autism: Examining Intrinsic and Extrinsic Factors in Children and Adolescents Enrolled in a National ASD Cohort

Discernment of possible sex-based variations in presentations of autism spectrum disorder (ASD) symptoms is limited by smaller female samples with ASD and confounds with ASD ascertainment. A large national cohort of individuals with autism, SPARK, allowed parent report data to be leveraged to examine whether intrinsic child characteristics and extrinsic factors differentially impact males and females with ASD. Small but consistent sex differences in individuals with ASD emerged related to both intrinsic and extrinsic factors, with different markers for males and females. Language concerns in males may make discernment of ASD more straightforward, while early motor concerns in females may hamper diagnosis as such delays are not identified within traditional ASD diagnostic criteria.

Sex Differences in the Developmental Trajectories of Autism Spectrum Disorder

Purpose of Review

Females and males are disproportionately diagnosed with autism, a sex difference that has historically represented this neurodevelopmental condition. The current review examines lifespan developmental trajectories of autism based on sex to elucidate behavioral phenotypic differences that may contribute to differential rates of diagnosis.

Recent Findings

We review sex differences in diagnostic criteria: social communication and restricted interests/repetitive behaviors (RRBs). Results suggest RRBs are more indicative of a diagnosis in males, whereas social differences are more indicative of a diagnosis in females. Factors contributing to a later diagnosis in females include social strengths (camouflaging) and diagnostic overshadowing.

Summary

Sex differences in diagnostic criteria may contribute to differential rates of identification in males and females. Sex differences are most pronounced when assessing naturalistic social communication instead of reliance on standardized measure. Numerous future directions are identified including increasing samples of sub-threshold autistic females and evaluating longitudinal sex differences.

Roadblocks and detours on pathways to a clinical diagnosis of autism for girls and women: A qualitative secondary analysis

BACKGROUND

Autism is not always considered for girls and women until later along their clinical diagnostic pathways. Misdiagnosis or late diagnosis can pose significant disadvantages with respect to accessing timely health and autism-related services and supports. Understanding what contributes to roadblocks and detours along clinical pathways to an autism diagnosis can shed light on missed opportunities for earlier recognition.

OBJECTIVE

Our objective was to examine what contributed to roadblocks, detours, and missed opportunities for earlier recognition and clinical diagnosis of autism for girls and women.

DESIGN

We conducted a qualitative secondary analysis using data from a Canadian primary study that examined the health and healthcare experiences of autistic girls and women through interviews and focus groups.

METHODS

Transcript data of 22 girls and women clinically diagnosed with autism and 15 parents were analysed, drawing on reflexive thematic analysis procedures. Techniques included coding data both inductively based on descriptions of roadblocks and detours and deductively based on conceptualizations of sex and gender. Patterns of ideas were categorized into themes and the 'story' of each theme was refined through writing and discussing analytic memos, reflecting on sex and gender assumptions, and creating a visual map of clinical pathways.

RESULTS

Contributing factors to roadblocks, detours, and missed opportunities for earlier recognition and diagnosis were categorized as follows: (1) age of pre-diagnosis 'red flags' and 'signals'; (2) 'non-autism' mental health diagnoses first; (3) narrow understandings of autism based on male stereotypes; and (4) unavailable and unaffordable diagnostic services.

CONCLUSION

Professionals providing developmental, mental health, educational, and/or employment supports can be more attuned to nuanced autism presentations. Research in collaboration with autistic girls and women and their childhood caregivers can help to identify examples of nuanced autistic features and how context plays a role in how these are experienced and navigated.

Linear discriminant analysis of phenotypic data for classifying autism spectrum disorder by diagnosis and sex

Autism Spectrum Disorder (ASD) is a developmental condition characterized by social and communication differences. Recent research suggests ASD affects 1-in-44 children in the United States. ASD is diagnosed more commonly in males, though it is unclear whether this diagnostic disparity is a result of a biological predisposition or limitations in diagnostic tools, or both. One hypothesis centers on the ‘female protective effect,’ which is the theory that females are biologically more resistant to the autism phenotype than males. In this examination, phenotypic data were acquired and combined from four leading research institutions and subjected to multivariate linear discriminant analysis. A linear discriminant model was trained on the training set and then deployed on the test set to predict group membership. Multivariate analyses of variance were performed to confirm the significance of the overall analysis, and individual analyses of variance were performed to confirm the significance of each of the resulting linear discriminant axes. Two discriminant dimensions were identified between the groups: a dimension separating groups by the diagnosis of ASD (LD1: 87% of variance explained); and a dimension reflective of a diagnosis-by-sex interaction (LD2: 11% of variance explained). The strongest discriminant coefficients for the first discriminant axis divided the sample in domains with known differences between ASD and comparison groups, such as social difficulties and restricted repetitive behavior. The discriminant coefficients for the second discriminant axis reveal a more nuanced disparity between boys with ASD and girls with ASD, including executive functioning and high-order behavioral domains as the dominant discriminators. These results indicate that phenotypic differences between males and females with and without ASD are identifiable using parent report measures, which could be utilized to provide additional specificity to the diagnosis of ASD in female patients, potentially leading to more targeted clinical strategies and therapeutic interventions. The study helps to isolate a phenotypic basis for future empirical work on the female protective effect using neuroimaging, EEG, and genomic methodologies.

Exclusion of females in autism research: Empirical evidence for a "leaky" recruitment-to-research pipeline

Autism spectrum disorder (ASD) is characterized by challenges in social communication and the presence of repetitive behaviors or restricted interests. Notably, males are four times as likely as females to be diagnosed with autism. Despite efforts to increase representation and characterization of autistic females, research studies consistently enroll small samples of females, or exclude females altogether. Importantly, researchers often rely on standardized measures to confirm diagnosis prior to enrollment in research studies. We retrospectively analyzed the effects of one such measure (Autism Diagnostic Observation Schedule, ADOS) on research inclusion/exclusion rates by sex in autistic adults, all of whom had a preexisting community diagnosis of autism (n = 145, 95 male, 50 female). Using the ADOS as a confirmatory diagnostic measure resulted in the exclusion of autistic females at a rate over 2.5 times higher than that of autistic males. We compared sex ratios in our sample to those in other large, publically available datasets that rely either on community diagnosis (6 datasets, total n = 42,209) or standardized assessments (2 datasets, total n = 214) to determine eligibility of participants for research. Reliance on community diagnosis rather than confirmatory diagnostic assessments resulted in significantly more equal sex ratios. These results provide evidence for a "leaky" recruitment-to-research pipeline for females in autism research. LAY SUMMARY: Despite efforts to increase the representation of autistic females in research, studies consistently enroll small samples of females or exclude females altogether. We find that despite making up almost 50% of the initially recruited sample based upon self-report of community diagnosis, autistic females are disproportonately excluded from research participation as a result of commonly used autism diagnostic measures. In our sample, and several other publically available datasets, reliance on community diagnosis resulted in significantly more equal sex ratios.

Developmental Milestones as Early Indicators of Twice-Exceptionality

Twice-exceptional individuals are those who have high cognitive ability in one or more areas, but also have a diagnosed disability. The needs of these individuals likely differ from those with high cognitive ability without a disability and those who solely have a disability. Intervening early can offer exceptional benefits for twice-exceptional individuals, but this has proved challenging due to the high cognitive abilities masking disabilities. This study explores if parent-reported developmental milestones can predict the number of disabilities diagnosed for an individual, including Autism Spectrum Disorder (ASD), Attention-Deficit/Hyperactivity Disorder (ADHD), and Specific Learning Disorder (SLD). Using a clinical sample of about 1,300 individuals, we used a Bayesian cumulative logistic model to explore if developmental milestones can predict the number of diagnoses after controlling for IQ and age. Study results showed that when an individual began to count and read informed predictions for the number of future diagnoses in the clinical sample. Implications for future study and practitioners are discussed in further detail.

Sensory features in autism: Findings from a large population-based surveillance system

Sensory features (i.e., atypical responses to sensory stimuli) are included in the current diagnostic criteria for autism spectrum disorder. Yet, large population-based studies have not examined these features. This study aimed to determine the prevalence of sensory features among autistic children, and examine associations between sensory features, demographics, and co-occurring problems in other areas. Analysis for this study included a sample comprised of 25,627 four- or eight-year-old autistic children identified through the multistate Autism and Developmental Disabilities Monitoring Network (2006-2014). We calculated the prevalence of sensory features and applied multilevel logistic regression modeling. The majority (74%; 95% confidence interval: 73.5%-74.5%) of the children studied had documented sensory features. In a multivariable model, children who were male and those whose mothers had more years of education had higher odds of documented sensory features. Children from several racial and ethnic minority groups had lower odds of documented sensory features than White, non-Hispanic children. Cognitive problems were not significantly related to sensory features. Problems related to adaptive behavior, emotional states, aggression, attention, fear, motor development, eating, and sleeping were associated with higher odds of having documented sensory features. Results from a large, population-based sample indicate a high prevalence of sensory features in autistic children, as well as relationships between sensory features and co-occurring problems. This study also pointed to potential disparities in the identification of sensory features, which should be examined in future research. Disparities should also be considered clinically to avoid reduced access to supports for sensory features and related functional problems. LAY SUMMARY: In a large, population-based sample of 25,627 autistic children, 74% had documented differences in how they respond to sensation. We also identified significant associations of sensory features with adaptive behavior and problems in other domains. Sensory features were less common among girls, children of color, and children of mothers with fewer years of education, suggesting potential disparities in identification.

Towards equitable diagnoses for autism and attention-deficit/hyperactivity disorder across sexes and genders

PURPOSE OF REVIEW

Sex/gender-related factors contribute to contextual issues influencing the recognition of autism and attention-deficit/hyperactivity disorder (ADHD), and modulate how neurodevelopmental characteristics are manifested. This review summarizes the empirical literature to provide directions for improving clinical diagnostic practices.

RECENT FINDINGS

Timing of autism and/or ADHD diagnosis, particularly in girls/women, is related to the individual's developmental characteristics and co-occurring diagnoses, and expectancy, alongside gender stereotype biases, of referral sources and clinicians. This is further compounded by sex and gender modulations of behavioural presentations. The emerging 'female autism phenotype' concept may serve as a helpful illustration of nuanced autism phenotypes, but should not be viewed as essential features of autism in a particular sex or gender. These nuanced phenotypes that can present across sexes and genders include heightened attention to socially salient stimuli, friendship and social groups, richness in language expression, and more reciprocal behaviours. The nuanced female-predominant ADHD phenotypes are characterized by subtle expressions in hyperactivity-impulsivity (e.g., hyper-verbal behaviours). Optimizing neurodevelopmental diagnoses across sexes and genders also requires an understanding of sex-related and gender-related variations in developmental trajectories, including compensation/masking efforts, and the influences of co-occurring conditions on clinical presentations.

SUMMARY

Equitable diagnoses across sexes and genders for autism and ADHD require understanding of the nuanced presentations and the Gestalt clinical-developmental profiles, and addressing contextual biases that influence diagnostic practices.