Electrical brain stimulation (EBS) is a popular new technique used to change brain function and treat neurological, psychiatric and psychological disorders. In this article, M. E. Héroux and colleagues analyzed whether the published literature, which is dominated by positive results, reflects the experience of researchers using EBS. Specifically, the authors wanted to know whether researchers are able to reproduce published EBS effects and whether they engage in, but fail to report, questionable research practices. To address these questions, 976 researchers were invited to complete an online survey and 100 randomly-selected published EBS papers were evaluated. The presented results in this study confirmed that questionable research practices and poor reproducibility are present in EBS studies. The authors concluded that more rigorous approaches are needed so that reproducible brain stimulation methods can be devised and applied.
This is a very interesting example from a clinical research area. Unfortunately, there are only a very few possibilities for preclinical research to compare reproducibility across dozens of studies. However, if these existed, what would be the degree of variability we would see?