Date of Award


Document Type

Open Access Thesis




College of Arts and Sciences

First Advisor

Jane E. Roberts


disorders are the most prevalent disorders in children and adolescents, affecting approximately 15-20% of individuals under the age of 18 (Salum et al, 2013). Clinical subgroups, like autism spectrum disorder (ASD) and fragile X syndrome (FXS), have an elevated risk of a co-occurring anxiety disorder. Despite the elevated risk of anxiety in these groups, few research studies have investigated the rates and predictors of anxiety disorders in adolescents with these ASD and FXS. In the current study, participants included males with FXS (n=31) or ASD (n=20) aged 16 to 24. Measures included the Children’s Interview for Psychiatric Symptoms-Parent Version (P-ChIPS), the Autism Diagnostic Observation Schedule-2 (ADOS-2), and the Leiter International Performance Scale-Revised (Leiter-R). Descriptive statistics indicated that 48% of the FXS adolescents met criteria for an anxiety disorder compared with 50% in ASD. Additionally, 13% of the FXS and 30% of the ASD sample met for multiple anxiety disorders. Across the FXS and ASD groups 35% versus 15% met for Specific Phobia, 12% versus 30% met for Social Phobia and 33% versus 40% met for GAD, respectively. T-tests showed no significant differences within and across groups for those meeting criteria for an anxiety disorder verses those not meeting criteria for age, NVIQ growth scores, and ASD severity. Results of the binary logistic regression did not show age, NVIQ growth scores, or ASD severity as significant predictors of any anxiety disorder across FXS and ASD. Lastly, approximately 40% of participants with FXS who met criteria for an anxiety disorder were prescribed medications for anxiety, as compared iv to 20% of the participants with ASD who met criteria for an anxiety disorder. Logistic regression results showed that taking anxiety medications were not significantly predictive of meeting criteria for an anxiety diagnosis however anxiety medication use was predictive of group diagnosis. Our primary finding is that approximately half of the FXS and ASD sample met for an anxiety disorder based on DSM-V criteria. Further, This study is the first that directly compares rates of anxiety disorders across adolescents and adults with FXS and idiopathic ASD within a small range of ages, intellectual ability, and autism severity. Reduced rates of anxiety disorders may be indicative of adolescent or young adult males with lower intellectual functioning who have FXS or ASD.