Before formal publication in a scholarly journal, scientific and medical articles are traditionally “peer reviewed.” In this process, the journal’s editors take advice from various experts—called “referees”—who have assessed the paper and may identify weaknesses in its assumptions, methods, and conclusions. Typically a journal will only publish an article once the editors are satisfied that the authors have addressed referees’ concerns.

Because this process can be lengthy, authors use the bioRxiv service to make their manuscripts available as “preprints” before peer review, allowing other scientists to see, discuss, and comment on the findings immediately. Readers should therefore be aware that articles on bioRxiv have not been finalized by authors, might contain errors, and report information that has not yet been accepted or endorsed in any way by the scientific or medical community.