Integration and FQT Defect Rates

  Integration Defect Rates (defects/KSLOC) FQT Defect Rates (defects/KSLOC) Number of Data Points
Norm (all languages) 33 3 543
Average (Ada) 24 1 153
Average (C++) 31 3 23

Source: CTA follow-on study, 1991

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From the Script: SLIDE 8 - Integration and FQT Defect Rates

Another study, from CTA, gathered data from four programming domains. The average error rates across the four domains for both Ada and C++ projects are shown here. The integration error rates include all errors caught from the start of integration defect testing to the completion of Formal Qualification Test defect testing. The FQT error rate includes only those errors found during the FQT process.

The C++ project data included information from 23 projects by seven firms, all of whom had been using C++, UNIX, and object-oriented techniques for over 2 years. All projects were new developments, with application sizes ranging from 25 to 500 KSLOCS.

This study demonstrates Ada's strong integration capabilities. Large, complicated programs can be broken down, developed by distributed work groups, and integrated with remarkable efficiency. [CTA, p.10]