Usefulness of Clinical T-Score of Continuous Performance Test for Differential Diagnosis: among Attention-Deficit Hyperactivity Disorder, Depressive Disorder, Anxiety Disorder, and Tic Disorder

ABSTRACT

OBJECTIVES: This study was conducted to examine whether there are qualitative differences in attention problem among children with various psychiatric disorders, including attention-deficit hyperactivity disorder (ADHD), depressive disorder, anxiety disorder, and tic disorder using clinical ADHD diagnostic system (ADS) T-scores. METHODS: The subjects were 794 outpatient children aged from 5 to 15 years, including 540 children with ADHD, 95 children with depressive disorder, 86 children with anxiety disorder, and 73 children with tic disorder. Clinical T-scores on the ADS were calculated using the mean and standard deviations of four ADS variables for the ADHD group. RESULTS: All four groups had T-scores on the ADS in the abnormal range. However, when comparing the clinical Tscores, the children with depressive and anxiety disorders performed better than the children with ADHD. We also found that although the four groups seemed to be similar in terms of clinical T-scores for omission and commission erros, there were significant differences in clinical T-scores for reaction time and the standard deviation of response time (RT) between the ADHD and other groups. CONCLUSIONS: We concluded that inattention and impulsivity might not be specific only to ADHD and that the clinical T-scores of RT and standard deviation of RT on the ADS could be used to discriminate between ADHD and other clinical groups.