What is Defect Based Testing Technique?

Defect Based Software Testing Technique:

A defect based testing technique is a technique where test cases are derived on the basis of defects. Instead of using the traditional requirements documents or the use cases (Specification based techniques), this strategy uses the defects to base their test cases.

The categorized list of defects (called as defect taxonomy) is being used. The coverage using this technique is not very systematic, hence deriving your test cases bases on this technique only, may not solve the purpose of quality deliverable. This technique can complement your test deriving conditions and can be taken as one of the option to increase the coverage of testing. Or in some other sense – This technique can be applied when all the test conditions and test cases are identified and we need some extra coverage or insight into testing.


Defect based technique can be used at any level of testing, but it is best suited in Systems Testing. We should base our test cases from the available defect taxonomies as well. These defects can be the production ones or the historical ones. Root cause analysis can also be used to baseline your test cases.

The 5 step plan to write the test cases through defect based testing techniques can be:

  1. Identify and prioritize the requirements
  2. Identify and collect all the defects
  3. Brainstorm on the defect
  4. Link the defect to the requirement
  5. Write the test conditions / test cases based on the linked defects.