System Usability Scale

A widely used, standardized questionnaire consisting of 10 items that measures perceived usability of a system. Developed by John Brooke in 1986, SUS provides a "quick and dirty" reliable measure of usability. Each item uses a 5-point Likert scale, and the final score ranges from 0 to 100. In accessibility research, SUS is frequently used to evaluate assistive technologies and accessible interfaces, though researchers should be aware that positive response bias among participants with disabilities may inflate scores compared to objective performance measures.