Requirement metrics. An initial literature survey on measurement approaches for requirement specifications

High quality requirements documents are an essential success factor for software development projects. Requirements are the starting point for each development step, thus requirements of bad quality can have severe consequences for the whole development process. Therefore, it is important to evaluate the quality of the requirements as early as possible. Metrics are a means to evaluate the quality of the requirements. Requirements can have different quality aspects like readability, completeness, verifiability, etc, but how can a requirements engineer decide whether a quality attribute is fulfilled or not. This document presents the results of a literature survey on software requirements metrics. The survey was focused on metrics that are defined to measure the overall quality of a requirements document. Of special interest were metrics that can be applied in requirements documents written in natural language and written with Use Case.