What are preprints? A Short Guide to Early Scientific Publishing

They are research papers shared before peer review, enabling rapid and open dissemination of findings. While valuable for transparency and early feedback, they also carry risks if misinterpreted. Understanding their role is key to responsible science communication.

As discussed in a recent post, the quality and integrity of scientific research are upheld through a rigorous and often lengthy process known as peer review. This process begins once a manuscript is submitted to a journal and assesses the validity and reliability of the science being published. While essential, peer review can significantly slow down the journey towards publication (which can take months or even years), thereby postponing the dissemination of new research findings to the broader scientific community.

Places for non-peer-reviewed research

To address this bottleneck – exacerbated by issues such as a shortage of qualified researchers willing to serve voluntarily as peer reviewers and the lack of transparency in the typically “blind” peer review system – many researchers have increasingly turned to preprint publishing. In recent years, there has been a notable rise in the practice of sharing manuscripts publicly before they undergo peer review.

Numerous online platforms (a list is available here) now serve as repositories for these pre-publication versions of scientific articles. The first of these, arXiv, was launched in 1991 at the Los Alamos National Laboratory in the U.S. to circulate preprints in the high-energy physics research field. Since then, many other platforms have emerged, particularly over the last two decades – for example, bioRxiv (pronounced “bio-archive”) for life sciences research.

Pros of publishing preprints

Publishing manuscripts on preprint servers offers several advantages to authors and the broader scientific community.

For researchers, it allows them to establish authorship and priority of their work upon publication in a peer-reviewed journal. It also opens their findings to feedback and critique from peers in the field, potentially improving the manuscript. Early exposure may also enhance media coverage and even boost citations.

For the broader community, it promotes the unrestricted circulation of scientific results by bypassing journal paywalls, thus contributing to “green open access” (also known as self-archiving).

However, the adoption of preprints varies across disciplines. Fields such as physics, biology, and – as we have seen especially with the Covid-19 pandemic – medicine have embraced preprints extensively. In contrast, many other disciplines have yet to develop a strong ‘preprint culture’. One possible reason for this reluctance is that not all journals accept submissions that have previously appeared as preprints, thus discouraging their use.

Cons of publishing preprints

While the practice of publishing preprints offers clear benefits – including the open and rapid dissemination of data and insights – they are not without drawbacks. Perhaps the most notable concern stems from its greatest strength: the absence of peer review. Without this layer of expert evaluation, the quality and reliability of the data presented in preprints can vary widely, introducing potential risks.

This becomes particularly problematic when unreviewed research attracts media attention and widely spreads before experts have a chance to identify potential errors or misinterpretations. During the pandemic, for instance, preprints played a crucial role in the swift communication of emerging knowledge about the virus, the disease, potential treatments, and vaccine development. However, some preprints containing inaccurate or flawed information also gained widespread public visibility, only to be retracted or discredited, undermining public trust in scientific research.

Transparency is key

Journalists should approach them with caution to minimise the risk of spreading incorrect information when reporting on promising and newsworthy findings presented in preprints. This involves critically assessing the information contained in the manuscripts and consulting subject-matter experts when necessary. Importantly, journalists should clearly communicate to audiences that preprints have not yet undergone peer review and, as such, carry a greater degree of uncertainty compared to published research. Maintaining transparency about the status of these studies is essential for preserving public trust in science while supporting the timely and open sharing of scientific knowledge.