Impact Analysis

Describes the version management and the impact analysis when a requirement is modified.


When the input evolves, the coverage relationships evolves too and output must be updated in the following cases:

  • if a requirement has been tagged as deleted, but still remains in the new version of the input,
  • if requirement has been removed from input,
  • If the version of a requirement has been updated,
  • If a new requirement has been created.

The impact analysis consists in analyzing the all the coverage errors after such modifications : identify all elements of output that shall be updated. REQCHECKER™ includes an impact analysis presented in the Coverage Matrix.


In this example :

  • I1 has been updated in version 1. O1 must be updated : its content must be checked and maybe updated. Then its version must be updated to 1.
  • I2 has been tagged as deleted. O2 must be updated : the coverage must be removed, and maybe the artifact removed if it becomes unused.
  • O6 covers a requirement that has been removed. Either the coverage must be removed and maybe the artifact removed, either a requirement is missing.

If requirement in not fully covered, for example I3, its status is PARTIAL.

A coverage error occurs when :

  • An requirement is never covered, for example I4. The error is named NO_COVERAGE_ERROR.
  • An requirement is covered with a wrong version, for example I1. The error is named BAD_VERSION_ERROR.
  • An requirement is covered since it has been deleted, for example I2. The error is named DELETED_COVERED_ERROR.
  • An artifact covers a missing requirement, for example O6. The error is named NO_STATEMENT_ERROR.
  • An requirement is defined twice, for example I4. The error is named SEVERAL_STAT_ERROR.

See Status List Page.

Automatic version

The software automatically creates a version for each requirement when no version is defined by the statement. The automatic version is a 6 characters length hash number, for example 5CJYS3.

The hash is computed from text and picture read from documents. The automatic version is not dependent from the following changes:

  • case sensitive change,
  • bullet modification,
  • spaces.

The 6 characters length collision probabilities are:

  • If you update the requirement once, then update the coverage, the probability to skip the modification is 0.0000004%.
  • If you update the requirement 10 times, then update the coverage, the probability to get the same hash is 0.000016%.