The Problem Preprints Solve
The traditional peer review cycle takes, on average, 6–18 months from submission to publication. During that time, research findings that could inform clinical decisions, policy discussions, public health responses, or follow-on research remain locked in a review process invisible to the world.
COVID-19 made this problem viscerally apparent. The scientific community's rapid response to the pandemic was driven, in substantial part, by preprints, bioRxiv and medRxiv published thousands of COVID-related manuscripts within days of submission, enabling the global research community to begin building on and critiquing findings months before formal publication would have been possible.
Preprint servers did not suddenly become important in 2020. They have been central to some disciplines for decades, arXiv launched in 1991 in physics and has been the primary mode of research distribution in physics, mathematics, and computer science ever since. But the pandemic accelerated awareness across disciplines that previously had no preprint culture.
How Preprint Servers Work
A preprint is a version of a paper that has not yet completed peer review. It is submitted directly to a preprint server by the author, not through a journal, and made publicly available within hours or days.
What preprint servers provide:
- Immediate public access: Anyone in the world can read the paper on day of deposition
- A citable DOI: Most major servers issue DOIs immediately, making the preprint citable as a research output
- Google Scholar indexing: Preprints appear in Google Scholar search results, often before any peer-reviewed version exists
- Moderation (not peer review): Most servers perform basic checks for completeness and scope but do not peer review, the scientific community provides post-publication review through comments, citations, and formal letters
What preprint servers do not provide:
- Peer review quality signals
- Journal affiliation or Impact Factor
- Guaranteed accuracy (findings may change during formal review)
The Major Servers by Discipline
arXiv (arxiv.org)
The oldest and most established preprint server, covering physics, mathematics, computer science, statistics, quantitative biology, quantitative finance, and economics. Highly respected, in physics, a paper on arXiv is often considered equivalent to publication for priority purposes. Moderates for scope and basic quality; does not charge fees.
bioRxiv (biorxiv.org) and medRxiv (medrxiv.org)
bioRxiv covers the life sciences broadly; medRxiv focuses on health sciences and medicine. Both are operated by Cold Spring Harbor Laboratory. medRxiv includes a content screening process that checks for ethical concerns and ensures papers are not making unsupported clinical recommendations before deposition. Both are free and highly indexed.
SSRN (ssrn.com)
The Social Science Research Network covers economics, law, social sciences, and humanities. Now owned by Elsevier, but free to deposit. Largest social science preprint database with millions of papers.
PsyArXiv (psyarxiv.com)
Psychology and related fields. Part of the Center for Open Science (OSS) infrastructure. Widely used in behavioural and cognitive science.
Research Square (researchsquare.com)
Multidisciplinary and positioned as the preprint home for papers that will be submitted to Springer Nature journals. Offers author services including language editing and figure preparation.
ESSOAr (essoar.org)
Earth and space sciences. Supported by the American Geophysical Union.
Zenodo (zenodo.org)
Not exclusively a preprint server, but accepts preprints alongside datasets, software, presentations, and other research outputs. Useful for researchers in disciplines without a dedicated server.
The Strategic Case for Preprint Deposition
1. Immediate citation priority
When a paper is deposited as a preprint, it establishes the date of the finding. If another researcher publishes a similar finding later, the preprint demonstrates your temporal priority. In competitive fields, this matters significantly.
2. Community feedback before formal submission
Preprints attract comments, tweets, and informal peer review from the research community. Substantive feedback received before formal submission can genuinely improve a paper, catching errors, identifying missing citations, and strengthening the framing for peer reviewers.
3. Visibility during the review gap
A paper under review for 12 months is unknown to the world. Its preprint is indexed in Google Scholar, potentially cited in other papers, and visible to researchers who might otherwise have missed it entirely by the time formal publication happened.
4. Open Access by default
Preprints are always Open Access. The citation and engagement advantages of Open Access, documented consistently across disciplines, apply from day of preprint deposition.
The Risks to Understand
Findings may change during peer review. If a preprint presents results that are later substantially revised or retracted through formal review, the preprint remains on the server. Label preprints clearly, and update the record with a link to the final published version once it exists.
Some journals have prior publication policies. Check the Sherpa Romeo database or the specific journal's author guidelines before depositing a preprint, some journals (though a declining minority) consider preprint deposition as prior publication and will not accept the manuscript. Most major journals explicitly permit preprints.
Misleading preprints in health and clinical fields carry real risk. In clinical medicine and public health, findings presented in preprints can be picked up by media before peer review has identified errors. This is a disciplinary responsibility issue, be accurate, appropriately caveated, and responsive to corrections.
Updating and Linking Your Preprint Record
When your paper is formally published:
- Upload the final accepted manuscript (post-print) or link to the published version on the preprint server
- Update your ORCID profile to link both the preprint and the published version
- Update your Google Scholar profile if the preprint and published version appear as separate entries, merge them so citations consolidate
Strategic preprint deposition is one of the fastest and lowest-cost visibility interventions available to any researcher. If you are not using preprint servers, you are missing months of visibility window for every paper you publish. The Digital Visibility Clinic covers your full dissemination strategy across preprint servers, repositories, and open access channels. Read our companion guide on Open Access and research discoverability for the complete picture.
