Association between Self-Reported and Clinician-Rated Anxiety in Adults with Autism Spectrum Disorder and Adults with Schizophrenia Spectrum Disorders
Objectives: The current study investigated demographic factors and clinical features as predictors of clinician-assigned anxiety diagnoses transdiagnostically. It was hypothesized that self-report ratings of anxiety in both ASD and SSD diagnostic groups would be associated with increased probability of meeting diagnostic criteria for a comorbid anxiety disorder on a clinician-rated measure.
Methods: Collected as part of a larger research study, the sample included 36 adults with ASD (27 male; M=25.06 years old) and 27 adults with SSD (22 male; M=23.29 years old). Diagnoses were confirmed by the Autism Diagnostic Observation Schedule, Second Edition (ADOS-2) and Structured Clinical Interview for DSM-IV (SCID-IV). IQ was measured using the WASI-II (ASD M=105.11, SD=15.51; SSD M=95.96, SD=11.43). Anxious symptomology was measured using the self-report Beck Anxiety Inventory (BAI), and the clinician-rated Mini International Neuropsychiatric Interview (MINI). A dichotomous (yes/no) variable was created to indicate the presence (ANX)/absence (N-ANX) of an anxiety disorder based on the MINI. ASD symptomology was measured by the ADOS-2 Severity Score (DSM-5 ADOS-2 Module-4 algorithm) and SRS-2 self-report and SSD symptomology was measured by the SAPS/SANS.
Results: An independent-samples t-test was conducted to investigate differences in self-report ratings between the ANX-group and N-ANX-group. As expected, the ANX (M=13.28, SD=9.49) and the N-ANX (M=7.56, SD=9.63) groups differed significantly; t(61)=2.14, p=.04. There was a significant point bi-serial correlation between clinician and self-report ratings, rpb(63)=-.26, p=.04, with anxiety diagnoses associated with higher ratings on the self-report. To further explore this relationship, a binomial logistic regression was performed to ascertain the effects of age, gender, IQ, level of autism and SSD symptomology, and self-report ratings on the likelihood of receiving an anxiety diagnosis on the MINI. The logistic regression model was statistically significant, χ2(7)=55.23, p<.001. The model explained 87.5% (Nagelkerke R2) of the variance in clinician ratings and correctly classified 94.8% of cases (sensitivity 94.1%, specificity 95.1%, positive predictive value 83.3%, negative predictive value 93%). Of the seven predictors, three were statistically significant: gender (B=-5.16,Waldχ2 =5.14,p=.02), ADOS-2 Severity Score (B=.52,Waldχ2=6.47,p=.01), and SRS-2 Total Score (B=-.358,Waldχ2 =10.31, p=.001). Males had 5.16 times lower odds of being diagnosed with anxiety than females. Increasing ADOS-2 severity scores were associated with an increased likelihood of clinician-rated diagnosis but increasing SRS-2 scores were associated with a reduced likelihood. Age and SSD symptomology approached significance (p=.06 and p=.07), respectively.
Conclusions: Results demonstrate an association between self-report and clinician ratings of anxiety, but surprisingly, self-report of anxiety was less predictive of an anxiety diagnosis than other factors such as gender or ASD symptomology. SSD symptomology was approaching significance as a predictor, which may suggest that individuals, regardless of primary diagnosis, are reporting symptomology related to both ASD and SSS that lead to a greater likelihood of a clinician-rated anxiety diagnosis.