Applying Usability Measures to Assess Textbooks

Abstract

The assessment of usability is a common task for human factors professionals. The System Usability Scale (SUS) is a survey tool that has been supported empirically as a psychometrically robust, valid and highly adaptive way to measure subjective usability. One area in which the SUS has not been applied yet, but could have direct and important applicability, is in the assessment of textbooks. Although usability (and a SUS score) is not typically thought of as a textbook metric, the International Organization for Standardization (ISO) metrics of effectiveness, efficiency and satisfaction map well onto key attributes that describe a good textbook. Here we describe the results of an initial effort to explore using the SUS to measure textbook usability. A total of 319 participants completed the SUS and indicated the usability of the textbooks required in their classes in a given semester. In total, participants rated 169 unique textbook titles. Results showed that only 32% of Science, Technology, Engineering and Math (STEM) textbooks were rated as acceptable, with almost twice as many non-STEM textbooks (63%) rated as acceptable. Specific attributes of textbook design that support usability are discussed.