A preprint is a complete scientific manuscript uploaded by its authors to a public platform. This is a contrast to the more traditional method of research publication, where a manuscript undergoes peer review prior to publication in a journal. With preprints, this release to the public typically happens before peer review is completed, although the preprint may be the same version or an earlier version of a manuscript sent to a journal for peer review and publication.
- A major advantage of preprints is time. The average total duration of peer review is 4 months; preprinting allows authors to release their findings immediately. This means that publications reach other researchers and the public more quickly. In situations like the COVID-19 pandemic, this timeline has been essential for the rapid communication of information.
- The immediacy of a preprint allows authors to stake a claim over their findings, establishing that they discovered something first.
- Early publication through preprinting can also allow authors to gain valuable feedback from their colleagues prior to publishing, which ultimately improves the quality of the final published work.
- A preprinted article has not withstood the scrutiny of traditional peer review. Because peer review implies that several members of the researcher’s community have read the article and generally agree with the conclusions, there may be additional considerations to keep in mind when assessing the validity of a preprint’s findings.
- Preprints can often contain preliminary results that will continue to be revised during the peer review process before final publication.
- If you’re new to reading research, it can be difficult to tell whether what you’re reading is trustworthy. This is one reason we include a message above preprints on our server - this helps the reader to consider the lack of peer review when deciding whether to trust an article’s results.
What to watch for
- Other types of review. Peer review and endorsement by a journal is not the only element of credibility that a paper might have, and it has its own shortcomings. A preprint will sometimes generate commentary from other scientists in the field - either on the preprint server itself, on dedicated preprint review platforms, or on social media. These “community reviews” can contribute important context and call out the strengths and weaknesses of the paper.
- Where is the article posted? Not all preprint servers or repositories have mechanisms in place to ensure the basic scientific validity of what they post. Platforms should clearly state their standards for posting in their Editorial Policies or FAQs. At Research Square, for example, all posted articles are screened for violations of ethical norms, pseudoscience, or overblown and controversial claims.
- What biases might exist in the article? As with any research article, there is a potential for bias to drive a study’s results or their interpretation. A thorough peer review process is designed to account for these limitations, but in its absence, they may be more prevalent or less readily acknowledged.
- Metrics. Some article-level metrics, such as those around citations, may help readers to understand how the study is being received and referenced by other researchers in the field.
Discover more Explainers and other Reader Resources on the Research Square Blog.