What Is Change Impact Analysis in Software Testing?

During the software development process, it is often a common experience for your client to come up with new ideas or changes that they want to implement in the software project. This can happen either during any of the six phases of the SDLC process such as the requirement phase, design phase, implementation and coding phase, testing phase, deployment phase, or maintenance phase. Regardless of the phase where the change is introduced, It is very important to note that even the slightest of changes made can have a huge effect on the general functioning of the software. In some cases, if the change is not properly scrutinized before implementation, it can lead to disruption of existing codes thereby causing damages to the entire software. It is, therefore, crucial to carry out effective analysis of the possible impacts that the new changes will have on the software generally. In this tutorial, we would be looking at impact analysis in software testing and how it can be properly accomplished.

So, are you ready? Let’s begin!

What is impact analysis in software testing?

In software testing, impact analysis is described as the process of evaluating the changes recommended or changes made in the existing code, features, modules, or functionality of the software product. It implies that you are trying to figure out the likely impacts that the changes will bring to the software product.

What are the benefits of impact analysis?

There are numerous advantages of carrying out impact analysis in the software development process. These benefits include:

1. Impact analysis enables you to determine the probable risks accompanied by the recommended changes on the features, code, or module.
2. It helps you to estimate the effort that would be required to effect the changes on the software as well as how long it will take to effect the change.
3. Prototype pretesting: Depending on the nature of the change to be implemented, you might need to develop a prototype to test the effects before applying it to the software as some changes might lead to damage of modules or disruption of codes. This comes about as a result of impact analysis.
4. Impact analysis enables you to pinpoint all the documents, modules, code,s or features that might need to be adjusted for the change to be implemented on the software product.
5. The impact analysis helps to avoid serious damages that could result from implementing certain changes on the system including loss of money, or even human life.
6. It helps the team of developers to devise a proper plan to implement the change in the most effective manner.
7. Improved testing efficiency and product quality: impact analysis helps to prevent loss of key features or modules that could have occurred due to implementing changes that are detrimental to the software. This helps to ensure easy tracking of features as well as enhance the general product quality.
8. Reduced testing time: due to impact analysis, the tester can figure out the exact modules and codes that need to be tested without having to go through the stress of dealing with errors in codes and functionalities.
9. Impact analysis helps to make the testing process more cost-effective.

What are the steps in carrying out change impact analysis?

Team preparation:

The first step that you need to take in conducting impact analysis is to set up your team of professionals. Now it depends on the kind of change that is being implemented. Your team can comprise testers, software developers, programmers as well as business analysts. Each of the professionals has a role to play towards achieving an effective impact analysis. The business analyst describes the changes to be made after consulting with the stakeholders. The programmers are there to effect changes on the algorithms or codes as required, the developers will spearhead changes on the features or functionalities of the software. The testers are there to carry out a regression test to check for the general performance of the software after the change is effected. There is also a need for effective communication amongst all the members of the team to avoid unnecessary hitches. For instance, let’s say a programmer implements some changes on the codes of a particular feature M. Assuming that, before the change, feature M and feature N were related in functioning but after the change was implemented, feature M is now related to feature P, the tester might not be aware and this may make the testing process tedious and futile for the tester.

Inspection of high-level modules:

After setting up your team, the first thing you want to check for is the high-level modules of the software system. Appropriate team members should analyze the high-level modules that are likely to be altered by the change. What positive and negative impacts could result from implementing the recommended change?

Inspection of low-level modules:

After the high-level modules have been inspected, the next step is to inspect the low-level modules. This is done to determine the likely effects that the change will have on the low-level modules. At this stage, there is a need to gather all the data on the likely effects for both the high-level and low-level modules. The data obtained can be recorded as a word file or excel sheet. The recorded data will now be used for evaluation in the next step.

Evaluation of change impact:

In this step, you begin a critical assessment of every impact from the recorded data, including positive and negative impacts that will result from the implementation of the change. You do this for both the high-level and low-level modules. If the change will have adverse effects on the modules, then there may be a need to review the requirements of the change to see how it can be best implemented. If the recommended change is considered healthy for the software, it is then adopted for implementation. Moreover, for instances where the change might damage the overall functionality of the system, you might need to consult the client and propose a takeback. It might be that your client just saw a particular feature from another software out there and they want you to implement the same feature in their software without considering certain key factors such as configuration, operating system and the likes. As such, you need to be professional in your approach.

Regression testing:

After the implementation process, the software is tested again to check for overall performance through a process called regression testing. Regression testing is the process of re-running the software to verify that the codes, features, and modules of the software are functioning well and not impacted by the implemented change. It is the test carried out after the change has been effected to ensure that the software is working properly and that the functionality is not disrupted by the change.

What is an impact analysis document?

An impact analysis document is a written document showing the various reports recorded during the impact analysis. It can be presented in the form of a Word document or an excel file.

Features of an impact analysis document

1.   It briefly explains the major issues with implementing the change.
2.  It shows a list of all the impacts of the change on the software including the positive and negative impacts.
3. It shows the complexity of work to be done in order to effect change.
4. It describes all the functionalities to be tested.
5.   It shows all the new test cases resulting from implementing the change.

What is the importance of an impact analysis document?

1. The document supplies data about the changes in the codes, features, or functionality of the software.
2. The document enables software testers to effectively plan and conduct tests with the provided information about the change.
3. The document helps to reduce the testing time for testers as they can now easily identify and test for specific modules as well as sub-modules that have changed.
4. The document will enable testers to use only standard impact analysis reports.
5. The impact analysis document helps testers as well as developers to have a clear picture of all the modules present in the system.
6. The document enables easy bug detection.

Application of impact analysis in development phase

Developers have a very important role to play in impact analysis. A developer must possess appropriate skills that will enable him to carry out his role effectively during the impact analysis process. There is a need for the developer to study the different modules critically to determine how they interdependent or relate with each other. The developer must also ensure that he sticks to the resources provided in the impact analysis documents. After effecting the change, the developer needs to update the impact analysis document with his new finding to ensure proper communication amongst the team members. The developer’s approach is first to review the software product as a whole and not just unit modules or features. Next, he must have a full grasp of the total software framework and relationship between individual modules. The developer should affect the changes in a manner that will minimize the risk of bug detection while performing the testing process.

Application of impact analysis in testing phase

The role of testers cannot be overemphasized in impact analysis testing. As a tester, you need to fully understand in detail all the changes that have been effected on the features, codes, or modules of the software. This will help to avoid conducting a test on parts of the software that were not altered. This will also enable you to determine the key features and modules that require testing thereby making the testing process faster to do. You also have to look at other aspects of the software that could probably be affected by the change.

Conclusion:

So far, we have learned about change impact analysis as well as its benefits. We have also learned about the steps in performing change impact analysis. As a professional in software development, you need to fully understand the concept of impact analysis to help you provide the best services to your clients.