Replication

Most scientific studies are aimed to test different hypotheses, deepen our understanding of various phenomena, provide information about a specific process, or uncover the works of some mechanism. Eventually, the results of a research experiment are aimed at equipping us with knowledge about ourselves and the world around us. Some of the factors that affect the results originate from the underlying research question, while others are related to researchers' specific choices when performing the study. To discover whether the results obtained in an experiment are reproducible, scientists should perform a replication study. Replication is the act of performing a study on a new sample to test whether the original scientific findings are recreated. In recent years, the importance of replications has been emphasized across fields, from social sciences to cancer biology. In this article, we review how replications are defined, executed, and evaluated. This highlights the complexities researchers face when performing and assessing the success of replication attempts. We discuss what affects a study's replicability and highlight progress made in brain research following the appreciation of replications' contribution to the field.