Independent testing refers to the involvement of a separate team, distinct from the developers, in testing activities. Such a team aims to eliminate author bias and increase the effectiveness of defect and failure detection. This approach is often preferred as it promotes objectivity and reduces the likelihood of overlooking errors or flaws.
Table of Contents
- Degrees of Independence
- Independent Testing in Test Levels
- Independent Testing Dependency on SDLC
- Benefits of Independent Testing
- Limitations of Independent Testing
- Video Tutorial
Degrees of Independence
Individuals can perform testing tasks in a dedicated testing role or by individuals in other roles, such as customers. Achieving a certain degree of independence in testing often enhances the tester's effectiveness in identifying defects, as it mitigates the cognitive biases that may be present in the author's perspective. However, it is essential to note that independence does not necessarily replace familiarity, and developers can also effectively identify defects in their code.
Testing has various degrees of independence, each offering different levels of objectivity and effectiveness. These degrees of independence are as follows, listed from the lowest to the highest level:
- No independent testers: In this scenario, the only form of testing available is that which is conducted by the developers who wrote the code. This is the lowest level of independence, as the person responsible for writing the software is also responsible for testing it.
- Independent testers within the team: This involves developers testing the products of their colleagues within the development or project teams. This offers a higher level of independence than no independent testers, as the tester is not the author of the code being tested.
- Independent test team within the organization: A dedicated testing team reporting to a project or executive management. This team is responsible for testing all software products within the organization, offering a higher degree of independence and objectivity than Independent testers within the team.
- Independent testers from the business organization or user community or with specializations: This degree of independence involves specialists in specific types of testing, such as usability, security, performance, regulatory/compliance, or portability. They are not members of the development team and can provide high objectivity.
- Independent testers from external organizations: This level of independence involves hiring testers from outside the organization, either on-site (in-house) or off-site (outsourcing). This offers the highest level of independence, as the testers have no stake in the product's success or failure.
Independent Testing in Test Levels
It is often recommended to incorporate multiple test levels into a project to ensure comprehensive testing and high-quality software. To achieve greater objectivity, independent testers who are not involved in the development process should handle some of these levels.
It is still essential for developers to participate in testing, particularly at the lower levels, as this allows them to exercise control over the quality of their work and to catch defects before they propagate to higher levels of testing. A more effective and well-rounded testing process can be achieved by incorporating both independent testing and developer involvement.
Independent Testing Dependency on SDLC
The implementation of independent testing varies depending on the software development lifecycle model used.
In Agile development, testers may be integrated into the development team. In some organizations utilizing Agile methods, these testers may be considered part of a larger independent testing team.
Moreover, in such organizations, product owners may perform acceptance testing at the end of each iteration to validate user stories. This can be seen as a form of independent testing. The product owners are not directly involved in the development process and can provide a fresh perspective on the software's usability and functionality.
Benefits of Independent Testing
There are numerous benefits to incorporating independent testing into a software development project. These include:
- Unbiased Testing: Independent testers bring different perspectives and technical backgrounds to testing activities, allowing them to recognize different kinds of failures than developers who may be influenced by their own cognitive biases.
- Challenging Stakeholder Assumptions: Independent testers can verify, challenge, or disprove assumptions made by stakeholders during the specification and implementation of the system, ensuring that the product meets the actual needs and requirements of its users.
- Lack of Organization Pressure: Independent testers hired from outside the organization can report objectively and impartially about the system under test without political or other pressures from the company that hired them.
- Cost-Effectiveness: Hiring resources from specialized testing organizations reduces training and employee benefits costs while also providing the flexibility to scale resources up or down as needed throughout the project development cycle.
- Better Product Quality: Experienced and skilled testers provided through independent testing can lead to higher-quality software products that meet user needs and expectations.
Incorporating independent testing into a software development project can lead to more comprehensive testing, better product quality, and increased cost-effectiveness.
Limitations of Independent Testing
While there are many benefits to independent testing, it's important to note that this approach has potential drawbacks. These limitations may include:
- Team Isolation and Conflicts: Isolation from the development team may lead to a lack of collaboration, delays in providing feedback to the development team, or an adversarial relationship with the development team. This can create a perception of independent testers as a bottleneck to the development process.
- Developers loose sense of responsibility: Developers may lose a sense of responsibility for the quality, assuming that it is solely the responsibility of independent testers.
- Difficulty Gathering Information: Independent testers may lack critical information about the test object necessary for comprehensive testing. This can lead to gaps in test coverage and potential defects being missed.
It's essential to consider these limitations when deciding whether or not to incorporate independent testing into a software development project. While the benefits of independent testing can be significant, it's crucial to ensure that the testing process is integrated effectively with the development process to avoid any negative consequences.