The "Preprint Era" and the Misleading Information if A Critical Review is not Performed

The most common definition of preprint is that it is a publication of a complete work which has been published or posted on a server dedicated to this type of communication (preprint server). All of these documents have in common that has not been peer-reviewed. Until few years ago, medical journals would not agree to publish anything that would have been available in a full version prior to submission, and the only decision that could be made in that circumstance was rejection. The rationale for this is that meta-analysis efforts could be undermined by the risk of duplicate counts of trials included in systematic reviews (and hence of patients). However, in recent years, several journals are available to receive works that have been pre-published as preprint. One of the key points to modify this scientific point of view is that researchers can immediately communicate their findings, facilitating quick feedback and promoting collaboration. By doing so, they can also reduce publication bias and improve methodological transparency. However, by circumventing the peer review process, it is possible to spread erroneous data or misinterpretations and suffering the subsequent consequences. These issues have never been highlighted better than during the ongoing COVID-19 pandemic. Researchers have inundated the literature with preprints as interim measures to satisfy the desperate need for knowledge about the disease. These unreviewed articles initially outnumbered those published in conventional journals and helped guide the general scientific community at the onset of the pandemic. However, it has been observed that not all the results were well processed, requiring several retractions by the authors. As a consequence, and as part of the future of science, it is necessary to promote the scientific criteria to discern all the information provided by this type of repositories to avoid these problems in the future