The Relationship Between Socialization and Externalizing Problems in ASD and VCFS

Background:  

Addressing both core symptoms of autism spectrum disorder (ASD) and associated symptoms of ASD has become increasingly important (Lord & McGee, 2001). A commonly associated feature of ASD is that individuals often exhibit externalizing problems (Volker et al., 2010). It is important to understand the relationship between externalizing problems and core symptoms of ASD. 

Objectives:  

To examine whether social functioning uniquely predicts externalizing problems in ASD, in relation to typically and atypically developing populations.

Methods:  

125 children and adolescents participated in this study: 34 with ASD, 34 typically developing (TD), and 58 with Velocardiofacial (VCFS / 22q11) syndrome. All diagnoses of ASD were confirmed using the ADOS-2, the ADI-R, and clinical judgment and VCFS diagnosis was confirmed with FISH analysis. Participants with VCFS did not have a comorbid diagnosis ASD, based on the ADI-R.

Externalizing behaviors were assessed with the BASC-2 Parent Rating Scale while social functioning was assessed with the socializations scores on the Vineland-II. IQ was measured by the WASI-II in the ASD and TD groups and by the WISC-III or the WAIS-IV in the VCFS group.

The ASD and TD groups were matched on chronological age (within 12 months) and Full Scale IQ scores (within one standard deviation) on the WASI-II.

Results:

Linear regressions assessed whether Socialization scores predicted Externalizing Problems. IQ was not significantly correlated with either measure in the ASD or TD groups and was thus not included in the regression. IQ was a significantly related to Socialization for the VCFS participants and was entered into the regression first.

For the ASD group, but not the TD group, socialization significantly predicted externalizing problems, β = -.619, P < .001, and socialization explained a significant proportion of variance (38.4%) in externalizing problems scores, R² = .384, F(1,32) = 19.93, p < .001.

For the VCS group socialization, but not IQ, significantly predicted externalizing problems β = -.328, P < .001, and socialization explained a significant proportion of variance (62.6%) in externalizing problems scores, R² = .626, F(1,55) = 35.499, p < .001.

Conclusions:  

Socialization abilities significantly predicted externalizing behaviors in both participants with ASD and VCFS. These results can inform assessment and such that interventions targeting externalizing behaviors should focus on promoting social functioning as well. This relationship does not appear to be unique to ASD, as it also occurs in participants with VCFS.