Measuring and understanding user experience: current state and future needs

Over the last two decades of Human-Computer Interaction, the research focus has shifted from usability to the more holistic concept of user experience (UX). Given the subjective nature of UX, emphasis is placed on psychological constructs which are not directly observable. Thus, methods are needed to adequately measure these complex experiences, among which self-reported survey scales are some of the most popular. However, the psychometric quality of those scales is not always known or (re-)investigated, which would be essential to have confidence in the findings obtained from them. Consequently, this thesis consists of four manuscripts investigating the measurement of UX from different perspectives and through the investigation of various survey scales. In particular, the first manuscript studies one crucial question from UX research, namely, how interface aesthetics affect users' subjective experience and their objective performance in the to-date understudied but increasingly popular context of smartphone devices. The second manuscript looks at the quality of a particular scale for measuring website aesthetics and considers the effect negatively formulated items have on scale quality by offering an alternative positive version. The third manuscript investigates how survey scales are currently used and reported on in a particular area of research, namely player experience (PX). Finally, the fourth manuscript examines the quality of one particular scale for measuring PX. Overall, this thesis provides insights into the current state of scale usage as a method in UX research while highlighting areas for future improvement.