Figure 1: Levels of Independence in Software Testing [2] 

The best results are usually achieved by combining multiple levels of independence. For example, unit tests may be performed by developers from the same team, system integration tests by an independent test team, and acceptance tests by an external team representing end users. [2] 

2. Similarities Between Testing and Auditing 

To better understand the importance of test independence, it is useful to examine the similarities between testing and auditing. 

Testing and auditing share significant similarities in purpose, process, and ethical principles: 

In corporate governance, audit and inspection units are not subordinate to the teams they audit. This is not only a regulatory requirement but also a sign of organizational maturity. Likewise, the principle of test independence is considered an indicator of organizational maturity and a strong quality culture. [4] 

TMMi (Test Maturity Model Integration) is an international maturity model used to assess and improve the maturity of software testing processes. It is considered the testing‑focused counterpart of CMMI, which defines an evolutionary improvement path for transforming immature processes into disciplined and mature ones. The principle of test independence is one of the key topics for TMMi. [1] [7] 

3. Benefits and Challenges of Independence 

4. Test Position in Agile Processes and the Risk of Losing Independence 

In Agile development processes, the principle of test independence takes on a different dimension. In Agile teams, quality is the responsibility of the entire team. Testers work alongside developers within the same team. Testing is part of the development team’s backlog, not a separate team’s plan. In this sense, Agile reduces some challenges associated with enforcing independence. [5] 

However, direct reporting of testers to development teams can compromise independence. This may shift testers’ focus from quality to delivery, weakening the testing perspective during development. In short, adherence to test independence and its benefits may be undermined. [1] 

Image 2: How Can Agile Transformation Be Successful [9] 

Is it possible to enjoy the advantages of Agile while maintaining compliance with the principle of test independence without conflict? 

5. Matrix Structure and Testing’s Position in the Organization 

A matrix organizational structure allows testers to report both to the development team and to centralized test management. This model offers the following advantages: 

Figure 2: Test Management with a Matrix Organizational Structure 

In such tasks, testers from different development teams are expected to participate. Centralized test management authority prevents conflicts and facilitates coordination. It also encourages participation in R&D projects and special task forces. 

In an Agile context with a matrix structure, testers are both part of development teams and members of a centralized test organization, contributing to multi-channel initiatives, knowledge sharing, and continuous improvement. [1] [3] 

6. Conclusion 

The principle of test independence is critical for improving software quality and ensuring impartial evaluation. Independence prevents conflicts of interest and builds trust. In Agile environments, independence should be balanced through tester integration with development teams and reporting to centralized test management. A recommended best practice is a matrix structure where testers work within development teams while also reporting to centralized test management. This approach combines the speed and collaboration benefits of Agile with the quality assurance provided by independence. [1] 

Ethical principles for independent auditors—Integrity, impartiality, confidentiality, professional competence, due care, and appropriate conduct—also apply to testers. These principles should be represented by a dedicated organizational structure, ensuring that test independence is preserved both in appearance and in practice. [4] 

References