Predictors of Adaptive Behavior in Adolescents with ASD

Background: Individuals with ASD demonstrate adaptive behavior difficulties regardless of intellectual functioning. Adaptive behavior is considered critical for performing tasks independently and better adaptive behavior skills are associated with greater opportunities for postsecondary employment. Prior research on adaptive behavior in adolescents with ASD typically includes only individuals with high functioning ASD (i.e., IQ > 70) and is from predominantly White samples. The present study aims to examine adaptive behavior in ASD in a large, diverse national sample of high school students with ASD across the full range of intellectual functioning and autism symptomology.

Objectives: The purpose of the current study was to (1) describe the communication, daily living skills, and socialization adaptive behavior profiles in adolescents with ASD and (2) examine the effects of intellectual functioning and autism symptomology on the adaptive behavior profiles in adolescents with ASD.

Methods: Adolescents with ASD (n=547) were part of a larger RCT of a comprehensive treatment model for high school students with ASD (mean chronological age= 16.2 years SD=1.44 years, range=14-21 years). 43% of the sample was non-White. The current study utilizes data collected prior to the intervention. Nonverbal IQ (NVIQ) was assessed using the Leiter International Performance Scales- 3^rd edition. Teachers completed the Vineland Adaptive Behavior Scales, 2^nd edition- Teacher Report as a measure of adaptive behavior and the Social Responsiveness Scale-2^nd edition (SRS-2) as a measure of autism symptomology. A multivariate multiple regression was performed to examine the extent to which intellectual functioning and autism symptomology predicted communication, daily living skills, and socialization domains of adaptive behavior.

Results: Findings indicated that adolescents with ASD had an average NVIQ of 85.5 (SD=27.2, range=30-141) and SRS-2 score of 70.4 (SD=12.2, range=39-110). The average adaptive behavior scores on communication were 77.6(SD=18.2., range=20-122), daily living skills were 80.8(SD=17.6, range=20-121), and socialization were 73.8(SD=14.4, range=30-122). Intellectual functioning and autism symptomology were significant predictors of adaptive behavior and accounted for 52% of the variance in communication, 52% of the variance in daily living skills, and 51% of the variance in socialization. Increases in NVIQ scores were associated with higher communication (B = .36, SE=.02, p <.001), daily living skills (B= .33, SE=.02, p <. 001), and socialization (B= .13, SE=.02, p <.001) standard scores controlling for autism symptomology. Higher autism symptomology was associated with lower communication (B = -.51, SE= .05, p <.001), daily living skills (B = -.50, SE=.50, p < .001), and socialization (B=-.71, SE=.04, p < .001) standard scores controlling for intellectual functioning.

Conclusions: This study represents the largest current sample of high school students with ASD. Adolescents with ASD in this diverse sample represented the full range of intellectual functioning and autism symptomology. On average, adaptive behavior scores were significantly below the standardization sample mean indicating that this sample demonstrates adaptive behavior difficulties. Higher intellectual functioning and lower autism symptomology were associated with greater adaptive behavior skills. Findings suggest the significance of adaptive behavior as an important area for targeted interventions during adolescence.