Comparison of empirical testing and walkthrough methods in user interface evaluation

We investigated the relative effectiveness of empirical usabitit y testing and individual and team walkthrough methods in identifying usability problems in two graphical user interface office systems. The findings were replicated across the two systems and show that the empirical testing condition identified the largest number of problems, and identified a significant number of relatively severe problems that were missed by the walkthrough conditions. Team walkthroughs achieved better results than individual walkthroughs in some areas. About a third of the significant usability problems identfled were common across all methods. Cost-effectiveness data show that empirical testing required the same or less time to identify each problem when compared to walkthroughs.