Rendex: A method for automated reviews of textual requirements

- Four measures of internal quality of textual requirements.
- Rendex - a measurement-based method for requirements ranking based on internal quality.
- Evaluation results of the ranking accuracy and the use of Rendex at four large companies.

Conducting requirements reviews before the start of software design is one of the central goals in requirements management. Fast and accurate reviews promise to facilitate software development process and mitigate technical risks of late design modifications. In large software development companies, however, it is difficult to conduct reviews as fast as needed, because the number of regularly incoming requirements is typically several thousand. Manually reviewing thousands of requirements is a time-consuming task and disrupts the process of continuous software development. As a consequence, software engineers review requirements in parallel with designing the software, thus partially accepting the technical risks. In this paper we present a measurement-based method for automating requirements reviews in large software development companies. The method, Rendex, is developed in an action research project in a large software development organization and evaluated in four large companies. The evaluation shows that the assessment results of Rendex have 73%-80% agreement with the manual assessment results of software engineers. Succeeding the evaluation, Rendex was integrated with the requirements management environment in two of the collaborating companies and is regularly used for proactive reviews of requirements.