What is a Requirements Traceability Matrix (RTM)?
A requirements traceability matrix is a document that demonstrates the relationship between requirements and other artifacts. It's used to prove that requirements have been fulfilled. And it typically documents requirements, tests, test results, and issues.
Read along or jump to the section that interests you most:
- What is Traceability?
- Why is Requirement Traceability Important?
- Who Needs Requirement Traceability?
- Creating a Requirement Traceability Matrix
- Using a Compliance Matrix
- Using a Risk Matrix
- Getting Started With Traceability Software
What is Traceability?
Requirements traceability is the ability to connect requirements to other artifacts — such as different types of software tests or bugs. It's used to track requirements — and prove that requirements have been fulfilled.
You Should Have Bidirectional Traceability
Bidirectional traceability is the ability to trace forward (e.g., from requirement to test case) and backward (e.g., from test case to requirement).
Traceability should be bidirectional. It establishes a relationship between two artifacts. And it’s important to be able to trace from one item to the next and back again.
That means tracing forward from requirements to source code to test cases to test runs to issues. And from issues back to requirements. You should also be able to trace back from requirements to business goals or objectives (to answer why the requirement is there).
Why is Requirement Traceability Important?
Requirements traceability is important to effectively manage your requirements.
Meeting Goals
When done well, traceability follows the life of a requirement. It starts at the time a requirement originates. And it continues on through fulfillment of the requirement. So, it makes sure that your requirements fulfill your original goals. For example, it gives you proof that you met compliance requirements.
Running the Right Tests
Requirement traceability also helps your quality assurance (QA) team understand what needs to be tested. This improves test coverage by mapping test cases back to each requirement. So, QA will be able to test all of the right things. And, as a result, you’ll be able to show that your requirements have been properly implemented.
Making Decisions
Traceability can also be used for decision-making throughout product development. You’ll be able to understand how product design will be impacted by requirements. And, if a requirement changes, you’ll be able to analyze the impact of that change across development.
[👉🏼 WHITE PAPER: ANALYZING THE IMPACT OF REQUIREMENTS CHANGE]
Managing Projects
Traceability is also useful for managing projects. You’ll know exactly how far you’ve progressed. And you’ll be able to manage the scope of your requirements. By linking your requirements to tests, you’ll understand how you can realistically meet those requirements and still ship on time.
So, you now know that requirement traceability is important. But what happens if you have weak traceability? Weak traceability can make it difficult to meet goals, run the right tests, make decisions, and manage projects.
[📄 WHITE PAPER: RECOGNIZING THE DANGER SIGNS OF WEAK TRACEABILITY]
Who Needs Requirement Traceability?
Every industry that produces software or hardware could use requirement traceability. But it's a pressing need for industries with something to prove.
Heavily regulated industries need traceability to prove compliance. These are typically quality- and safety-critical industries.
Embedded Systems Traceability
Traceability links artifacts — requirements, source code, tests, and issues — across the development lifecycle. This ensures that teams will be able to meet quality standards, produce safe products, and stay competitive.
Organizations in the embedded systems industry — an industry that combines hardware and software — need traceability. It helps them ensure safety and prove compliance.
[🙌🏻 WHITE PAPER: 5 EFFECTIVE TRACEABILITY COMPONENTS FOR EMBEDDED SYSTEMS DEVELOPMENT]
Examples include:
- Aerospace — to prove that aerial vehicles are safe to fly.
- Automotive — to prove that vehicles are safe to drive.
- Medical device — to prove that devices are safe for patient use.
Aerospace Traceability
One example is the aerospace industry. Software (e.g., flight data recorders) is increasingly embedded in hardware (e.g., a plane). It’s critical that the software upholds quality standards — or the plane could be at risk for a cyberattack.
Automotive Traceability
Another example is the automotive industry. Software (e.g., electronic door locks) is increasingly embedded in hardware (e.g., vehicles themselves). Standards for safety of these embedded systems have been around for decades — for example, the Motor Industry Software Reliability Association (MISRA) coding standard. And meeting these standards is critical.
Medical Device Traceability
Medical device developers need traceability, too. It helps them prove compliance and deliver quality products that are safe for patient use.
The medical device industry is heavily regulated by several agencies, including the FDA and ISO. Traceability — and especially a traceability matrix — makes it easier to maintain compliance and pass audits.
[👨🏽🔬 WHITE PAPER: 5 ESSENTIAL TRACEABILITY COMPONENTS FOR MEDICAL DEVICE DEVELOPMENT]
Traceability helps the medical device industry in other ways, too. It helps developers analyze risk and the impact of change. And that improves the quality of devices.
[FREE REPORT: THE STATE OF MEDICAL DEVICE DEVELOPMENT]
How to Create a Requirements Traceability Matrix (RTM)
Establishing traceability typically begins with creating a requirements traceability matrix.
Types of Traceability Matrices
There are different types of traceability matrices, depending on the desired use.
What Is a Test Matrix?
A traceability matrix in software testing — otherwise known as a test matrix — is used to prove that tests have been run.
It documents test cases, test runs, and test results. Requirements and issues may also be used in a test matrix.
A requirements traceability matrix typically includes, at minimum, requirements, test cases, test results, and issues.
How to Create a RTM
You can create a requirements test matrix (RTM) in Microsoft Excel. Or you can use specialized tools to accelerate the process.
There are three basic steps — no matter which tool you use.
- Define your goals.
- Establish your artifacts (and their relationships).
- Fill in the traceability matrix.
Benefits of Using a Requirements Traceability Matrix
There are six key benefits of using a requirements traceability matrix.
You’ll:
- Get visibility across development.
- Make better decisions (e.g., on requirements change).
- Accelerate release cycles.
- Rest easy knowing your requirements are fulfilled.
- Prove compliance faster.
- Pass audits without fear.
[🧭 GUIDE: EVERYTHING YOU NEED TO KNOW TO WRITE REQUIREMENTS WELL]
Using a Compliance Matrix
Need to prove compliance? Use a traceability matrix for compliance. This is also known as a compliance matrix.
Compliance regulations can be complicated. But when you track requirements from those regulations in a compliance matrix, it’s easier to understand what you need to develop and test. And that helps you track your tests and test results in relation to those requirements.
[💪🏽 WHITE PAPER: 6 EXERCISES TO STRENGTHEN TRACEABILITY]
If you’re in a heavily regulated industry, creating a compliance matrix can also take the pressure off your next audit. And if you create the traceability matrix as you develop, it’ll be much easier to document updates (e.g., issue resolution) and changes (e.g., requirements).
After all, you can’t stop the auditors from calling. But you can make it easier to demonstrate that you’ve fulfilled compliance regulations. And that will help you avoid additional costs during your audit.
Using a Risk Matrix
Need help managing risk? Use a traceability matrix to assess risk. This is also known as a risk matrix.
What Is a Risk Matrix?
A risk matrix is used to assess risk. It demonstrates severity and probability. And it calculates your risk score — the number that tells you how serious the risk is.
Using a risk matrix will help you:
- Get visibility into risk.
- Analyze risk — and decide what to do about it.
- Manage risk before it becomes a problem.
[👍🏼 WHITE PAPER: HOW TO SIMPLIFY RISK MANAGEMENT USING TRACEABILITY]
For example, if you have a known risk, you can set a requirement to avoid that risk. From there, you can create a requirements traceability matrix that shows how you are mitigating that risk.
If you need to unearth potential risks, you may do a failure modes and effects analysis (FMEA). You can do this by creating a risk matrix and using that matrix to decide what to do about risk — mitigate it, eliminate it, or accept it.
Or, you might have a compliance standard for classifying or avoiding risk — such as ISO 26262 or IEC 61508. You’ll need to use an automotive safety integrity level (ASIL) to meet ISO 26262. Or, you’ll need to use a safety integrity level (SIL) to meet IEC 61508.
A risk matrix will help you do risk analysis, such as ASIL and SIL.
Getting Started With Traceability Software
Traceability software makes it easier to establish relationships between artifacts. And using this software helps you create a traceability matrix — for compliance or to manage risk.
Some traceability software — such as Helix ALM — automates the process. You can even use Helix ALM for traceability with Jira issues.
In Helix ALM, you can create test cases from requirements, test runs from test cases, and issues from test runs. That instantly creates relationships — traceability — across your artifacts.
From there, all you need to do is run a traceability matrix report. And then you’ll have a traceability matrix you can use to:
- Understand project status.
- Make decisions if/when something changes.
- Release faster.
- Know your requirements are met.
- Prove compliance.
- Pass audits.