Test case design is the most important test activity with respect to test quality. For this reason, a large number of testing methods have been developed to assist the tester with the definition of appropriate, error-sensitive test data. Besides black-box tests, white-box tests are the most prevalent. In both cases, complete automation of test case design is difficult. Automation of black-box test is only meaningfully possible if a formal specification exists, and, due to the limits of symbolic execution, tools supporting white-box tests are limited to program code instrumentation and coverage measurement. Evolutionary testing is a promising approach for automating structure-oriented test case design completely. In many experiments, high coverage degrees were reached using evolutionary testing. In this paper we shall investigate the suitability of structure-based complexity measures to assess whether or not evolutionary testing is appropriate for the structure-oriented test of given te...