Gender Differences in Emotional and Behavioral Characteristics of Children with ASD

Background:

There is little research examining how gender affects behavioral and emotional characteristics of children with ASD.  Early studies suggest that girls with ASD may be more at risk than boys with ASD for developing internalizing and affective problems, which may be particularly pronounced in older girls.  It is critical to identify gender differences to determine if specific gender-targeted diagnostic and treatment methods should be developed to address the unique challenges that boys and girls with ASD experience.   

Objectives:

It is hypothesized that girls with ASD will present with more internalizing and affective problems than boys with ASD; increased age and level of intellectual functioning will contribute to higher internalizing and affective problems; and gender will interact with these factors, with older, higher-functioning girls exhibiting more problems.

Methods:

A record review from a Midwestern ASD assessment clinic was conducted.  Participants included 357 boys and 58 girls, ranging from 1.5 to 18.5 years old (mean age = 5.3 years).  There were no differences between girls and boys on age, level of intellectual disability, or ASD diagnosis.  Participants had been diagnosed with ASD by experienced clinicians, using DSM-IV criteria, parent interviews, and standardized caregiver-rated and clinician observational measures, including the parent-rated Child Behavior Checklist (CBCL).  

One-way ANOVAs were conducted to compare CBCL T-scores between girls and boys on several clusters of CBCL scales, including the syndrome scales, the internalizing, externalizing, and total problems domains, and the DSM oriented scales.  Correlations among gender, age, level of ID, and CBCL subscales were also examined.  A hierarchical stepwise linear regression was conducted to determine how much of the variance on particular scales could be accounted for by gender, age, level of intellectual disability, and the interaction between gender/age and gender/intellectual disability.   

Results:

There were no statistically significant differences between boys and girls with ASD on any of the CBCL scales, but there were differences on two of the CBCL scales with moderate effect sizes.  On the affective (p = .051, η² = .31) and sleep scales (p = .039, η² = .23), girls scored higher than boys.  Regression analyses indicated that gender did not significantly contribute to affective or sleep subscale scores, although age and level of ID did, with older children with higher levels of intellectual functioning exhibiting more affective and sleep problems.  Gender/age and gender/intellectual disability interactions did not contribute significantly to scores.  Age was significantly positively correlated with the anxiety/depression, sleep, affective, and ADHD scales, as well as the internalizing, externalizing, and total problems domains.  Level of ID was significantly negatively correlated with the anxiety/depression subscale and positively correlated with the attention and ADHD scales. 

Conclusions:  

Although there were fewer gender differences than expected, some interesting trends emerged, suggesting that girls with ASD may experience more affective and sleep problems than boys with ASD.  Age and intellectual functioning played a larger role in predicting these CBCL scores than gender, indicating the need for clinicians to consider these factors when assessing emotional and behavioral problems in individuals with ASD throughout the lifespan.