Obstacles to Comprehension in Usage Based Reading

Usage based reading (UBR) is a recent approach to object oriented software inspections. Like other scenario based reading (SBR) techniques it proposes a prescriptive reading procedure. However, the impact of such procedures upon comprehension is not well known, and consideration has not been given to established software cognition theories. This paper describes a study examining software comprehension in UBR inspections. Participants traced the events of a UML sequence diagram through Java source code while thinking aloud. An electronic interface collected real-time data, allowing the identification of "points of interest", which were categorised according to issues affecting participants\´ performance. Together with indicators of participants\´ cognitive processes, this suggests that adherence to UBR scenarios is non-trivial. While UBR can detect more critical defects, we argue that a re-think of its prescriptive nature, including the use of cognition support, is required before it can become a practical reading technique.