Risk-based testing (RBT) is an approach to software testing that seeks to maximize the effectiveness of a limited amount of testing resources. In a perfect world, an app development project would have no limitations placed on it, and every single component, feature, function, and line of code could be thoroughly tested.
This, however, is not reality. Oftentimes budget or time constraints force development teams to make the most out of the resources available to them. This is where risk-based testing can be an effective approach to software testing.
Getting the most out of all available resources is a big part of project management. If you’re managing a development project, you’ll likely want to know more about the risk-based testing approach, what it is, the steps involved, and the benefits of testing based on risk. Let’s take a closer look at risk-based testing now.
What is Risk-Based Testing (RBT)?
Risk-based testing is an approach to software testing that relies on risk assessments to determine the best allocation of testing resources. When you have a finite number of testing resources, you need to determine which parts of your application pose the biggest risk to your business, customers, staff, and brand identity.
Risk-based testing asks two very important questions. One, how likely is it that a bug will occur in the code of the application? Two, how big of an impact will that bug have on the business as a whole?
There are a number of different factors that are going to affect the risk level of your application. Some high-risk factors, for example, include:
- Complex code
- Code critical to the function of the app
- Code innovations
The risk level will also be highly affected by the type of feature or product being developed. For example, MedTech apps and FinTech apps inherently carry more risk than a gaming app since they handle very sensitive user data.
Bugs are fairly common occurrences in web and mobile app development projects. Even the simplest development projects often include multiple developers of varying skill levels, multiple codebases, and open-source technologies. All of these different situations increase the chance that a bug could occur in the application.
Risk-based testing helps your quality assurance team focus their software testing efforts on the parts of your project that are most likely to have a bug that will have the biggest impact on your business.
How is Risk Determined?
Risk assessment can be a tricky task. How do you determine which tests should be prioritized? The simplest answer is to look at the probability of a risk occurring and its potential impact. In a risk-based testing approach, you can look at three main aspects of your application to determine the risk level:
- Criticality
- Churn
- Complexity
Criticality
When risk management teams use the term criticality, they are referring to the measure of the impact a bug will have. Risk analysis shows that criticality is not typically distributed evenly throughout an application. Most applications have a core of critical code that the entire application depends on in order to function properly.
Criticality is an important measure to consider while performing risk analysis. Bugs that occur in the most critical areas of code will have far larger impacts than bugs that occur elsewhere. A bug in the app’s critical core code can lead to data loss, data exposure, and other serious consequences.
Churn
When we talk about risk assessment, the term churn refers to the number of changes made to any part of the application, although this term has different meanings when used in other contexts. Aspects of an application that receive a lot of attention, code changes, updates, etc., are more likely to contain bugs and other errors than parts of an application that never get touched.
While doing a risk analysis of your application, you should pay special attention to areas with a high amount of churn. Where churn is high, you should be doing more risk analysis and software testing to ensure that your application contains no bugs.
Complexity
Risk identification also looks at the complexity of an application’s code as a high-risk factor. Complex code is far more likely to contain errors than simple code. Measuring code complexity can seem like a subjective or difficult task, but you can simplify this process by looking at all of the possible paths in a function.
More paths mean more test cases are needed in order to fully test a function. Functions that require more test cases are more complex and thus possess greater potential for error.
The Steps In a Risk-Based Testing Approach
Now that you have a better understanding of what risk-based testing is and what constitutes a risk in apps and web services, let’s take a closer look at the process of risk-based testing. A risk-based testing approach includes five key steps:
- Risk Identification
- Risk Analysis
- Risk Response
- Test Scoping
- Testing
Risk Identification
The first step in a risk-based testing approach is to identify potential risks. Risk identification includes identifying, categorizing, and sorting the risks that pose the greatest threat.
Risk Analysis
Once risks have been identified, categorized, and sorted, risk analysis can begin. In this step, the identified risks will be discussed. The risks need to be analyzed in terms of likelihood and probable consequences. Based on this analysis, you will calculate the exposure you face. After this step, you should know which risks pose the greatest threat to your organization.
Risk Response
After risks have been identified and analyzed, you need to plan how you will respond to the risks you found. In this step, you will outline your test objectives and choose the most effective testing techniques. This is an important step if you want to have confidence in your test execution.
At this point in the risk-based testing process, you will also consider the time and financial costs of specific software testing versus the potential risk.
Test Scoping
This step is basically a final review before the testing stage actually begins. In this step, decision-makers need to agree on the scope of tests, the available budget for software testing, and individual responsibilities.
Testing
Once the risks have been identified, analyzed, and a scope and budget have been approved, it is time to perform the actual testing. In order to be financially effective, testing needs to strictly follow the scope and budget set out in the previous steps of the process. After this step is completed, the process can begin again as new code, features, and functionality are added to the app.
The Benefits of Risk-Based Testing
There are a lot of potential benefits to adopting a risk-based testing approach. We won’t go over every single possible benefit for your organization, but we will highlight three major benefits that you should be aware of:
- Productivity and cost-efficiency
- Faster time to market
- Clear information on testing coverage
Productivity and Cost-Efficiency
Thoroughly testing every aspect of an application takes a lot of time and costs a lot of money. Risk-based testing allows your testing team to be more efficient with their most valuable resource, time. Adopting risk-based testing will help improve the productivity of your testing efforts. Only areas that have a high probability of risk get tested, meaning your testers can focus their efforts on the most important parts of your app.
This approach is also far more cost-effective than traditional testing. It takes into account the finite nature of financial resources and allocates them based on need and risk factors. This cost efficiency helps organizations save money and spend their financial resources in a more targeted, logical manner.
Faster Time to Market
Risk-based testing helps get digital products to market faster. In today’s fast-paced, consumer-driven economy, being first to market can have a large impact on the future, long-term success of your organization. Since testing is more productive and targeted in a risk-based testing approach, the entire process moves quicker, meaning your products are on the market sooner.
Clear Information on Testing Coverage
What has and hasn’t been tested isn’t always clear when you’re working on a development project. Risk-based testing clearly documents which aspects of an app are receiving testing resources and attention so that you clearly understand what has been tested when. This information will influence future testing efforts and provide clarity to stakeholders.
Final Thoughts
A risk-based testing approach is a sensible way to allocate finite resources. In a perfect world, you would have unlimited time and money to conduct software testing, but this is rarely, if ever, the case. Risk-based testing highlights the areas that could cause the most trouble and allocates testing resources accordingly.
If you need help determining the best way to move forward with software testing, reach out to an app development partner. There are a lot of different approaches you could take. Rely on industry experience and technical expertise to guide you in the right direction.
