Attention-Deficit/Hyperactivity Disorder (ADHD) is difficult to diagnose due to the subjectivity of its symptoms and lack of specific assessment measures. Computerized tests of attention have recently been used as objective measures that may assist in the diagnosis of the disorder. The present study evaluated consistency between the Conners Parent Rating Scale and the Test of Variables of Attention (TOVA), which is a computerized test of attention designed to identify symptoms associated with ADHD, in children clinically diagnosed with ADHD (n = 28) and controls (n = 20). Our results showed that both the Conners and the TOVA indicated significant problem areas suggestive of an attention deficit in approximately 85% of children who were clinically diagnosed with ADHD. However, the TOVA also found attentional problems in approximately 30% of control children, whereas none of the controls scored abnormally on the Conners. As computerized measures are administered more frequently, there may be a risk of overdiagnosis and treatment of "ADHD" in normal children. A combined approach using questionnaires, clinical evaluation, and computerized tests of attention in the assessment of possible ADHD may provide the most accurate means of diagnosis.