Early Observation of Red Flags in 12-Month-Old Infant Siblings Later Diagnosed With Autism Spectrum Disorder

Purpose Valid and reliable screening tools are needed to improve early detection and optimize developmental outcomes for toddlers at risk for autism spectrum disorder (ASD). The current study aimed to evaluate the utility of the Systematic Observation of Red Flags (SORF) for ASD at 12 months of age in a sample of high-risk infant siblings of children with ASD. Method As part of a prospective, longitudinal study, we examined the sensitivity and specificity of the SORF at 12 months for predicting a diagnosis of ASD at 24 months in a sample of 122 infants, 31 of whom were diagnosed with ASD. Results The optimal SORF Composite cutoff score of 18 correctly identified 24 of the 31 twelve-month-olds who were diagnosed with ASD, yielding a sensitivity of .77 and a specificity of .76. The optimal SORF Red Flags cutoff score of 7 correctly identified 20 of the 31 infants, yielding a sensitivity of .65 and a specificity of .75. Conclusion This preliminary study demonstrates the potential of the SORF as an effective observational screening measure for 12-month-olds at risk for ASD with good discrimination, sensitivity, and specificity.

Performance of the Autism Observation Scale for Infants with community-ascertained infants showing early signs of autism

Often included within ‘high-risk sibling’ studies, the Autism Observation Scale for Infants (AOSI) has only one independent replication study and no evaluation with community-ascertained cohorts. We administered the AOSI and established clinical measures with 103 infants (68% male) at ‘high autism likelihood’ on the Social Attention and Communication Surveillance - Revised (SACS-R) tool, at 9–14 months of age and again 6 months later. AOSI Total scores showed adequate internal consistency and strong inter-rater agreement (live- or video-coded) and were approximately normally distributed at each visit. Modest significant associations presented between Time 1 AOSI scores and concurrent developmental/adaptive skills measures. Concurrent associations were stronger at Time 2, particularly between AOSI Total and Autism Diagnostic Observation Schedule (ADOS) Social Affect scores. AOSI scores were only moderately associated across Time 1 and 2 assessments, as were Time 1 AOSI with Time 2 ADOS scores. These data from a clinically indicated cohort broadly replicate previous AOSI validity accounts from ‘high-risk sibling’ studies, particularly beyond the first year. Strong inter-rater agreement indicates viable AOSI inclusion within protocols necessitating blinded evaluation (e.g. intervention trials). Moderate within-participant stability suggests that, like ‘high-risk siblings,’ community-ascertained infants experience variable early trajectories. Lay Abstract We investigated whether a commonly used research assessment – the Autism Observation Scale for Infants (AOSI) – accurately measures autism behaviours among infants showing early signs of autism identified within the community. The AOSI is often included in studies tracking the development of infants at increased likelihood of autism, such as the infant siblings of diagnosed children. However, the suitability of this measure has not previously been tested with community-referred infants. We administered the AOSI with infants when aged 9 to 14 months and again 6 months later. Our researchers – independent of the AOSI development team and newly trained on this measure – were able to administer the brief interactive assessment and score it accurately. The infants’ AOSI scores were linked to their scores on other established and validated clinical assessments, particularly at the second visit when average age was 18 months. Stronger correspondence of AOSI and other scores at this second visit suggests early autism behaviours are better established and more consistent by 18 months of age, even though these infants showed clear enough signs of possible autism to prompt referral to our study around 12 months of age. However, the moderate association of AOSI scores over time suggests that, like infant siblings – who mostly do not develop autism – community-identified infants showing early signs may also have variable developmental pathways in early life.

Motor atypicalities in infancy are associated with general developmental level at 2 years, but not autistic symptoms

Atypical motor development has frequently been reported in infants at elevated likelihood for autism spectrum disorder. However, no previous study has used detailed motion capture technology to compare infant siblings of children with autism spectrum disorder and infant siblings with no familial history of autism spectrum disorder. We investigated reaching movements during an interceptive action task in 10-month-old infants using kinematic data with high spatiotemporal resolution. The results indicated that several measures were different in infants at elevated likelihood. However, longitudinal analyses revealed that while specific infant motor measures (e.g. number of movement units) were related to broad measures of general developmental level in toddlerhood, the associations with later autism spectrum disorder symptomatology were not significant. These findings confirm that some aspects of motor functioning are atypical in infants at elevated likelihood for autism spectrum disorder, but provide no support for the view that these issues are specifically linked to autism spectrum disorder symptoms, but may rather reflect neurodevelopment more generally. Lay abstract Atypicalities in motor functioning are often observed in later born infant siblings of children with autism spectrum disorder. The goal of our study was to investigate motor functioning in infants with and without familial history of autism spectrum disorder. Specifically, we investigated how infants catch a ball that is rolling toward them following a non-straight path, a task that requires both efficient planning and execution. Their performance was measured using detailed three-dimensional motion capture technology. We found that several early motor functioning measures were different in infants with an older autistic sibling compared to controls. However, these early motor measures were not related to autistic symptoms at the age of 2 years. Instead, we found that some of the early motor measures were related to their subsequent non-social, general development. The findings of our study help us understand motor functioning early in life and how motor functioning is related to other aspects of development.