Applied Psychophysiology and Biofeedback, Vol. 23. No. 3.1998 Electroencephalographic and Psychometric Differences Between Boys with and Without Attention-Deficit/ Hyperactivity Disorder (ADHD): A Pilot Study Daniel J. Cox,1,2 Boris P. Kovatchev, James B. Morris, Jr., Cheralee Phillips, Rebecca J. Hill, and Larry Merkel Attention-Deficit/Hyperactivity Disorder (ADHD) is reported to have an incidence of 3-5%, and is associated with a variety of interpersonal, academic, and social problem behaviors. There is controversy as to whether ADHD is a learned behavioral or brain dysfunction. Research has explored a variety of measures to assess behavioral and brain dysfunctions in this population, with no consistent and clearly diagnostic results. We investigated whether a new psychometric and a new electroencephalographic procedure would clearly differentiate ADHD. The psychometric was based on DSM-IV criteria and the EEG measure was based on the assumption that ADHD interferes with cognitive transition from one discrete task to another. Parents of four ADHD boys (ages 8-12) and four age- and interest-matched non-ADHD boys completed the ADHD Symptom Inventory, while their sons' EEG was monitored during viewing of a video and reading of a book. For the ADHD boys, this was repeated a second time, 3 months later, to assess test-retest reliability. Both the psychometric and the EEG measures clearly differentiated the two samples (p's < .01) with no overlap in scores, were reliable over 3 months (r = .87), and were significantly correlated with one another (r = .85). While a small sample size, these robust, related and reliable findings suggest that both the psychometric and the psychophysiological EEG measures deserve further replication and exploration. KEY WORDS: attention deficit; hyperactivity; ADHD; psychometrics; EEG; electroencephalography; assess- ment; diagnosis. INTRODUCTION DSM-IV (APA, 1994) estimates the prevalence of Attention-Deficit/Hyperactivity Disorder (ADHD) in school-age children as 3% to 5%. Of all children referred for mental health services, one-third to one-half have been attributed to ADHD (Popper, 1988). Despite these high reported rates of prevalence, ADHD remains a controversial diagnosis. Critics 1University of Virginia Health Sciences Center, Charlottesville, Virginia 22908. 2 All correspondence should be addressed to Daniel J. Cox, Behavioral Medicine Center, Box 223, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908. 179 1090-0586/98/0900-O179$15.00/0 © 1998 Plenum Publishing Corporation