Test organization and independence

     A critical issue with testing is independence. [ISTQB05] The effectiveness of finding defects by testing and reviews can be improved by using independent testers. Options for
independence are:
  • Independent testers within the development teams.
  • Independent test team or group within the organization, reporting to project management or        executive management.
  • Independent testers from the business organization, user community and IT.
  • Independent test specialists for specific test targets such as usability testers, security
     testers or certification testers (who certify a software product against standards and
     regulations).
  • Independent testers outsourced or external to the organization. For large, complex or safety        critical projects, it is usually best to have multiple levels of testing, with some or all of the              levels done by independent testers. Development staff may participate in testing, especially at      the lower levels, but their lack of objectivity often limits their effectiveness. The independent        testers may have the authority to require and define test processes and rules, but testers              should take on such process-related roles only in the presence of a clear management                    mandate to do so.

The benefits of independence include:

   • Independent testers see other and different defects, and are unbiased.
   • An independent tester can verify assumptions people made during specification and
implementation of the system.

Drawbacks include:

  • Isolation from the development team (if treated as totally independent).
  • Independent testers may be the bottleneck as the last checkpoint.
  • If proper communication is not insured, developers may lose a sense of responsibility
    for quality.