The Effect of Interface Consistency and Cognitive Load on User Performance in an Information Search Task

Abstract

Although interface consistency is theorized to increase performance and user satisfaction, previous research has found mixed and often non-significant results. By controlling for the level of task difficulty, specifically the cognitive load, it is hoped that the study will explain the contradictory findings of past research. Eighty participants will be used in a 2×2×2 between-subjects factorial design. The study will manipulate the level of interface consistency, along with intrinsic and extraneous cognitive load imposed by the task. Objective performance measures of task completion time and error-rate along with the subjective measure of user satisfaction will be analyzed. It is expected that the high interface consistency condition will perform better than low interface consistency; in contrast, it is predicted that the low cognitive load condition will outperform the high cognitive load condition. Furthermore, it is predicted that the effect of consistency and cognitive load will interact causing the lack of interface consistency to be significantly more detrimental when paired with a high level of either form of cognitive load.