A Quick Test of Cognitive Speed for Comparing Processing Speed to Differentiate Adult Psychiatric Referrals With and Without Attention-Deficit/Hyperactivity Disorders

Abstract

This retrospective study used A Quick Test of Cognitive Speed (AQT) to compare processing speed and efficiency measures by adults with attention-deficit/hyperactivity disorder (ADHD) or non-ADHD psychiatric disorders and healthy controls. Color, form, and color-form combination naming tests were administered to 104 adults, ages 17-55 years, referred for psychiatric evaluation of possible ADHD. Thirty healthy adults were controls. Psychiatric intake procedures identified 64 adults with ADHD (ICD-10 and DSM-IV criteria) and 40 with mild psychiatric disorders without ADHD. The study was conducted from 2008 through 2010. At intake, color, form, and color-form combination naming times (seconds) were longer and overhead [color-form combination - (color + form)] was larger for patients with ADHD than for non-ADHD patients and controls. In the ADHD group, color and form measures were in the normal range. Color-form combination was in the slower-than-normal speed (60-70 seconds) and overhead, a processing-efficiency measure, in the atypical range (> 10 seconds). In the non-ADHD patient and control groups, all AQT measures were in the normal range. Analysis of variance with post hoc analysis of log-normal values for color, form, and color-form combination and time for overhead indicated significant (Bonferroni P < .01) mean differences between the ADHD and other groups, but not between the non-ADHD and control groups. When using fail criteria for either color-form combination or overhead, the sensitivity for the ADHD group was 89%. RESULTS support AQT as a possible complement to psychiatric intake procedures to differentiate adults with ADHD from those with mild psychiatric disorders, and they suggest that a controlled prospective study might be productive.