AQT cognitive speed and processing efficiency differentiate adults with and without ADHD: A preliminary study

Abstract

We evaluated the hypotheses that A Quick Test of Cognitive Speed (AQT) single- and dual-dimension naming speed measures would differentiate normal adults and adults with ADHD before medication and that there would be no differences between groups after stabilization with medication. Thirty adults with ADHD, aged 18-43, were evaluated with the AQT color (C), form (F) and color-form combination (CF) naming tests before and after medication with methylphenidate. Thirty age- and sex-matched normal adults served as controls. Among adults with ADHD, pre-medication naming times (s) for C, F, and CF were significantly longer and overhead [CF - (C + F)] significantly larger than post-medication. Before medication, C, F and CF naming and processing efficiency (overhead) (s) differed significantly between ADHD adults and controls. After medication, there were no significant differences between groups. When we used fail criteria for dual-dimension naming (> 60 s) and overhead (processing efficiency) (> + 6 s) together the sensitivity was 93% and specificity 100%. Within the study limitations, findings suggest that the processing-speed and efficiency measures in AQT may be used to screen adults for executive dysfunction and reduced cognitive control associated with ADHD.