Diagnosis or Not: Dimensional Autism Symptoms Are Related to Adaptive Social Skills across Adults with and without an Autism Diagnosis

Background: Adaptive social functioning is often impaired in individuals with Autism Spectrum Disorder (ASD) relative to their typically developing peers and is a well-established measure of functional outcomes for these individuals. This discrepancy cannot be explained entirely by intellectual functioning and seems to widen over the lifespan, as research suggests an increase in adaptive functioning deficits in ASD with age. However, less is known about the relationship between subclinical ASD symptoms (i.e., in those individuals who do not meet for a diagnosis but present with symptoms of ASD) and adaptive social skills, which may reveal important, unique needs of individuals who do not currently qualify for services by diagnostic standards. The current study seeks to fill this gap. We hypothesized that dimensional autism symptoms would explain variance in adaptive social skills, above and beyond an individual’s intellectual functioning, age, and ASD diagnosis, particularly for adults.

Objectives: To explore the relationship between a dimensional report of autism symptoms and adaptive social skills across individuals with and without autism, controlling for diagnosis.

Methods: A total of 74 participants with and without ASD were included in this study. This included 35 adults (40% Male; 60% ASD) and 39 children (85% Male; 64% ASD) who completed the Adaptive Behavior Assessment System, Second or Third Edition (ABAS) and Autism Spectrum Quotient (AQ). Analyses of adults and children were conducted separately to account for differences in raters and assessment versions. A series of hierarchical regressions were conducted for each age group with ABAS Social Domain standard score as the dependent variable. We first controlled for IQ, age, and ASD diagnosis, and then added the AQ total raw score in the subsequent model. Results of the model comparisons are reported.

Results: For adults, the covariates of IQ, age, and ASD diagnosis accounted for 30.6% of variance in adaptive social skills, although diagnosis was not statistically significant. Autism symptoms on the AQ accounted for an additional 14.7% of variance in adaptive social skills (ΔF_1,30 = 8.06, associated p < 0.01), indicating that greater ASD symptoms were associated with lower adaptive skills. There was no significant relationship between ABAS Social score and AQ total for children. See Table 1 for complete regression results.

Conclusions: This study suggests an association between dimensional autism symptoms and adaptive social skills for adults with and without ASD, even after controlling for ASD diagnosis. We did not find similar results for children, which may be a factor of age-related increases in adaptive skill deficits often seen in ASD. Our study is, however, limited by a small sample size. Future work should evaluate similar relationships with a focus on individuals without an ASD diagnosis, or below the “clinical cutoff” on the AQ, to confirm whether similar results are found within a purely sub-clinical population. In conclusion, this study sets the stage for future research to identify individuals who do not meet for a diagnosis of ASD but nonetheless display adaptive social skill deficits in their daily lives and may benefit from access to similar interventions.