Continuous test-based cloud certification uses tests to automatically and repeatedly evaluate whether a cloud service satisfies customer requirements over time. However, inaccurate tests can decrease customers' trust in test results and can lead to providers disputing results of test-based certification techniques. In this paper, we propose an approach how to evaluate the performance of test-based cloud certification techniques. Our method allows to infer conclusions about the general performance of test-based techniques, compare alternative techniques, and compare alternative configurations of test-based techniques. We present experimental results on how we used our approach to evaluate and compare exemplary test-based techniques which support the certification of requirements related to security, reliability and availability.