Context: Juristo et al. [7] published a literature review about testing technique experiments. The goal was to provide a picture of which techniques and aspects of techniques had been studied experimentally, and try to compile a body of knowledge on testing techniques. Goal: In this paper, we extend Juristo et al.'s study to cover the years from 2000 (where it ended) until 2013. Method: We have performed a systematic mapping study. Results: The situation in testing experimentation has not changed since Juristo et al.'s study. Conclusions: The research field has the same shortcomings.