Estimating Software Costs, 2nd Edition

Chapter 16Estimating Design Inspections

The defect-removal method of formal inspections was developed at IBM Kingston in the 1970s by Michael Fagan and his colleagues. The inspection process has more than 35 years of continuous data available and has proven to be one of the most effective and efficient defect-removal operations ever developed. As a general rule, formal inspections are about twice as effective in finding bugs as any known form of testing. Most forms of testing are less than 30 percent efficient in finding bugs, but formal inspections on average are more than 60 percent efficient and sometimes top 95 percent. As an additional benefit, inspections also raise testing efficiency levels and they serve as surprisingly effective defect ...