Journal of Attention Disorders

Despite the widespread use of methylphenidate (MPH) in the treatment of children with Attention Deficit Hyperactivity Disorder (ADHD), physicians often must rely on anecdotal observations and subjective reports to titrate MPH regimens. Many double-blind placebo-controlled medication trials have demonstrated treatment efficacy; however, the development of an effective clinical protocol that is reliably sensitive to dose-response relationships and can be used in office practice remains elusive. Using a double-blind placebo clinical protocol, and rank order analysis of instruments sensitive to ADHD symptoms, the MPH response patterns of 50 children with ADHD were analyzed using repeated measures multivariate analysis of variance. Several instru ments were sensitive in predicting response, and others revealed trends in the expected direction. The rank order rating analyses revealed robust differences between active drug conditions and placebo. Using cognitive rank order ratings, linear and quadratic MPH response patterns were identified, with the best dose for each group significantly different from that obtained for all other conditions.

A self-report questionnaire designed to identify children and adolescents with attention deficit hyperactivity disorder (ADHD) was developed by utilizing DSM-IV criteria and associated symptoms outlined in the research literature. The questionnaire was administered to 867 students who attended elementary, middle schools and high schools across the United States. Their responses were subjected to exploratory factor analysis and a three-factor solution was deemed appropriate for accounting for variation in the data. The factor scales were labeled Cognitive Inefficiency, Hyperactivity/Impulsivity, and Positive Impression. The respective scales contain items that are highly similar and produce stable results over time. Future research directions are outlined which bear on the validity of the questionnaire.

Several research studies have reported that the performance of children with attention deficit hyperactivity disorder (ADHD) on continuous performance tests (CPTs) is affected by comorbid anxiety. However, the specific anxiety domains/symptoms that affect CPT performance as well as the particular CPT performance measures have been inconsistent across studies. The present study examines CPT performance in 158 ADHD clinic-referred children using measures derived from signal detection theory. Regression analyses are conducted to examine whether any of the anxiety domains from the Revised Children's Manifest Anxiety Scale (RCMAS) account for variance on CPT performance measures. The main finding of these analyses is that physiological anxiety appears to increase response inhibition, whereas cognitive anxiety appears to decrease response inhibition. This finding suggests that physiological anxiety alone may be responsible for increased response inhibition/decreased impulsivity in children with comorbid anxiety. These results are interpreted in the context of Gray's model of a behavioral inhibition system