Reducing inspection interval in large-scale software development

We have found that, when software is developed by multiple, geographically separated teams, the cost-benefit trade-offs of software inspection change. In particular, this situation can significantly lengthen the inspection interval (calendar time needed to complete an inspection). Our research goal was to find a way to reduce the inspection interval without reducing inspection effectiveness. We believed that Internet technology offered some potential solutions, but we were not sure which technology to use nor what effects it would have on effectiveness. To conduct this research, we drew on the results of several empirical studies we had previously performed. These results clarified the role that meetings and individuals play in inspection effectiveness and interval. We conducted further studies showing that manual inspections without meetings were just as effective as manual inspections with them. On the basis of these and other findings and our understanding of Internet technology, we built an economical and effective tool that reduced the interval without reducing effectiveness. This tool, Hypercode, supports meetingless software inspections with geographically distributed reviewers. HyperCode is a platform independent tool, developed on top of an Internet browser, that integrates seamlessly into the current development process. By seamless, we mean the tool produces a paper flow that is almost identical to the current inspection process. HyperCode's acceptance by its user community has been excellent. Moreover, we estimate that using HyperCode has reduced the inspection interval by 20 to 25 percent. We believe that, had we focused solely on technology (without considering the information our studies had uncovered), we would have created a more complex, but not necessarily more effective tool. We probably would have supported group meetings, restricted each participant's access to review comments, and supported a wider variety of inspection methods. In other words, the principles derived from our empirical studies dramatically and successfully directed our search for a technological solution.