Quantitative EEG measurement of the scalp vertex theta/beta ratio (TBR) is marketed as a tool for use in the evaluation of patients who may have attention-deficit/hyperactivity disorder (ADHD). The American Academy of Neurology (AAN) recently assessed the literature about this tool. The assessment urged caution, considering that the TBR remains an investigational research tool at this time. This perspective comments further on that assessment and its rationale, and recommends a perspective for the clinician and payer.