Purpose
As a team stabilizes and scopes requirements at a high level, it is appropriate to refine the requirements to
lower-level requirements, specifying traceability between them.
Requirement Traceability Coverage is a way to measure that sufficient effort is put toward refining requirements that
are within scope, and that a broad perspective is taken in that refinement effort. If high-level requirements are
defined, bit not traced to lower-level requirements, the team may not be delivering correct functionality that the
stakeholders need and expect.
In some ways, this measure is a reciprocal of Untraced Requirements, though it used for a different purpose.
Definition
The percent of high-level requirements that have lower-level requirements traced to them over time.
Analysis
Use a line chart to show the percentage of requirement traceability coverage throughout the lifecycle. Depending on the
kind of project, the desired value is moderated by trending toward a learned mid-range value (that is, there is the
possibility of too much traceability).
If Requirement Traceability Coverage is low, it is an indication that the team may be building a system that is not
aligned with business needs.
Collection and reporting tools
Requirements traceability data can be obtained from a Requirements Traceability Matrix. Tools like Rational Team
Concert or Rational Insight provide full support for collecting and reporting traceability coverage data.
Pitfalls, advice, and countermeasures
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Requirements should be traced at least two levels, from low-level requirements to high-lever requirements and
technical requirements to low-level requirements. For example, product requirements traced to customer
requirements and product-component requirements traced to product requirements.
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When there is a change to the requirements, traceability coverage should be updated and the changes
incorporated.
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