Evaluation of the validity of the Autism Spectrum Quotient (AQ) in differentiating high-functioning autistic spectrum disorder from schizophrenia.
The aim of this study is to examine the validity of the Autism Spectrum Quotient (AQ) to differentiate high-functioning autistic spectrum disorder (ASD) from schizophrenia (SCH). The AQ was developed by Baron-Cohen et al. to measure autistic traits. In addition to the original AQ items, we created self-administered questions about psychotic symptoms (S-scale). We administered the modified AQ to 51 ASD patients and 46 SCH patients, and we compared these two groups in terms of total AQ score, AQ subscale scores and S-scale score. We applied receiver operating characteristic (ROC) curves to examine the discriminating power of the AQ. The mean total AQ score of the ASD group (32.6; SD=6.8; range: 8-48) was significantly higher than that of the SCH group (21.8; SD=7.4; range: 10-39) (p<0.001). All AQ subscale scores of the ASD group were significantly higher than those of the SCH group. By using a cut-off score of 29 for the AQ total score, we were able to correctly classify 80% of the subjects. At this cut-off, the positive and negative predictive values were 0.83 and 0.78, respectively. Inclusion of additional questions of the S-scale did not increase the power of differentiation. These results indicate that the usefulness of the AQ in differentiating high-functioning ASD from SCH is limited.
Department of Psychiatry and Neurology, Kobe University Graduate School of Medicine, Kobe, Japan. 054d541m@stu.kobe-u.ac.jp
Kenichi
K
Naito
Yusuke
Y
Matsui
Kiyoshi
K
Maeda
Kiwamu
K
Tanaka
D000293:Adolescent; D000328:Adult; D001321:Autistic Disorder / Q000175:diagnosis* / Q000523:psychology; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007361:Intelligence Tests; D008297:Male; D010045:Outpatients / Q000523:psychology; D010552:Personality Assessment / Q000592:standards*; D011594:Psychometrics / Q000592:standards*; D012372:ROC Curve; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D055815:Young Adult