Diagnoses of attention-deficit hyperactivity disorder (ADHD) are often made rapidly in physicians' offices without thorough assessment. We examined whether adults diagnosed with ADHD would score differently from controls on a modified Sensory Gating Inventory (SGI: Hetrick et al. in Schizophr Bull 38:178-191, 2012; Kisley et al. in Psychophysiol 41:604-612, 2004), which would facilitate rapid and easy preliminary assessment of ADHD status. The modified SGI was administered to 22 controls and 22 adults with physician diagnoses of ADHD. Analysis was performed on the 17 SGI items and the three categories to which they belong (Perceptual Modulation, Distractibility, and Over-Inclusion). The Distractibility category, and its individual items, showed large group differences. In spite of a relatively small sample size, we found large effect sizes between those with and without ADHD diagnoses. The SGI is a simple, quick, paper/pencil method that may be used to facilitate accurate diagnosis of individuals experiencing ADHD symptoms, which may be especially useful when evaluations are made in settings such as physicians' offices.