Lextant Usability Impact Score: A New, Objective Approach to Indexing Usability Issues
Gina M. Torelli, Alexandria Rossi Alvarez, Shasank Nagavarapu, Arisa Pruttianan, Richard del Rio, Bobby T. Nguyen · Proceedings of the Human Factors and Ergonomics Society Annual Meeting · 2018
An important step in evaluating system usability involves identifying and prioritizing usability issues to help guide future development. Many methods exist for this purpose, yet there is no consensus on which method is most applicable in a consulting environment. Traditionally, subjective scoring methods are used. These methods require subjective judgment from evaluators, which can result in low inter-rater reliability. Additionally, various domains use different subjective scoring methods, making it difficult to compare results across studies. The Lextant Usability Impact System (LUIS) was created to objectively prioritize usability issues and to be applicable across domains and comparable across studies. To increase reliability, LUIS objectively measures frequency, subjective probability, and severity separately prior to combining into an overall impact score. The results suggest that LUIS provides scores of higher granularity than traditional subjective scores and can be calculated by a single rater.