Replication crisis

The replication crisis, also known as the reproducibility or replicability crisis, refers to the growing number of published scientific results that other researchers have been unable to reproduce or verify. Because the reproducibility of empirical results is an essential part of the scientific method, such failures undermine the credibility of theories that build on them and can call into question substantial parts of scientific knowledge.

The replication crisis is frequently discussed in relation to psychology and medicine, wherein considerable efforts have been undertaken to reinvestigate the results of classic studies to determine whether they are reliable, and if they turn out not to be, the reasons for the failure. Data strongly indicate that other natural and social sciences are also affected.

The phrase "replication crisis" was coined in the early 2010s as part of a growing awareness of the problem. Considerations of causes and remedies have given rise to a new scientific discipline known as metascience, which uses methods of empirical research to examine empirical research practice.

Considerations about reproducibility can be placed into two categories. Reproducibility, in the narrow sense, refers to reexamining and validating the analysis of a given set of data. The second category, replication, involves repeating an existing experiment or study with new, independent data to verify the original conclusions.