Investigating the Effectiveness of Peer Code Review in Distributed Software Development

Code review is a potential means of improving software quality. To be effective, it depends on different factors, and many have been investigated in the literature to identify the scenarios in which it adds quality to the final code. However, factors associated with distributed software development, which is becoming increasingly common, have been little explored. Geographic distance can impose additional challenges to the reviewing process. We thus in this paper present the results of a quantitative study of the effectiveness of code review in a distributed software project involving 201 members. We investigate factors that can potentially influence the outcomes of peer code review. Our results show that a high number of changed lines of code tends to increase the review duration with a reduced number of messages, while the number of involved teams, locations, and participant reviewers generally improve reviewer contributions, but with a severe penalty to the duration.