Pre-print studies are studies that have been completed but haven't gone through the peer-review process that most scientific journals require for publishing. Pre-prints provide new data and information, which is important in a pandemic. However the details in a pre-print study, such as: how the study was designed and conducted, what sample sizes were included, what assumptions were made, and how calculations were done, have not been scrutinized by the journal's reviewers and editors. The process of scrutinizing a pre-print study is what the peer-review process consist of. Most websites that publish pre-print articles suggest that these articles should not be reported in the news as established information or used to guide clinical practice or health-related behavior. Until the studies are scrutinized by reviewers, they should not be assumed to be factually correct or inform any actions.

To be considered high quality, valid, significant, original, and suitable for publication in a scientific journal, studies must complete a peer-review process. As these published studies could potentially influence clinical practices and public health behaviour, this process acts as a filter to ensure every study meets the strict requirements of each journal, causing many studies not to be accepted or published once they go through peer reviews. Pre-print studies have not yet passed the peer-review process so scientists urge caution not to draw any conclusions from pre-print studies. The peer review and publication processes are time-consuming, frequently involving more than a year between submission and publication. The process is also highly competitive.  Peer-reviewed articles provide a trusted form of scientific communication. Even if you are unfamiliar with the topic or the scientists who authored a particular study, you can trust peer-reviewed work to meet certain standards of scientific quality. Since scientific knowledge is cumulative and builds on itself, this trust is particularly important. After submission of a pre-print study to a journal, the journal's editors send the article to several other scientists who work in the same field (i.e., the "peers" of peer review). Those reviewers provide feedback on the article and tell the editor whether or not they think the study is of high enough quality to be published. The authors may then revise their article and resubmit it for consideration. Only articles that meet good scientific standards (e.g., acknowledge and build upon other work in the field, rely on logical reasoning and well-designed studies, back up claims with evidence, etc.) are accepted for publication.