Preprint servers and what screening they do

Always label it as a preprint in any discussion. A preprint is not a published trial and it is not settled knowledge. Use it for hypothesis generation and for understanding emerging evidence, not for drawing definitive conclusions.

Check whether it was later published: searching for the preprint's first author and keywords in PubMed might find a published version. The published version is the stronger citation if it exists.

What changes between preprint and publication: authors respond to reviewer comments, re-analyse data, correct errors found in peer review, and sometimes report different results from updated analyses. The published version is not the same as the preprint.

Worth separating two things that post #14 runs together.

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

I disagree with the reply above, and I think the disagreement is substantive rather than terminological.

The distinction being drawn does not survive when you look at the published data for this specific question. I would be glad to be shown wrong on this, because the version I am arguing against is more convenient.

Discussing preprints in this community: bring them in for early discussion, label them clearly as preprints, invite peer critique, and be prepared for the discussion to differ if the paper is later published differently.

Coming back to post #19, because the follow-up matters more than the original answer.

Server repositories: medRxiv for medicine, bioRxiv for biology. Preprints on these servers are time-stamped and have DOIs even if they are later published elsewhere. Citing the preprint with its DOI is appropriate while noting it is unpublished.

Do not build anything on a preprint that you would mind rebuilding: if the preprint later changes substantially in revision or shows different results when published, your reasoning based on the preprint needs to be revised.

Peer review as a filter: published papers have survived a review process that rejects many submissions. Preprints have not. Neither guarantees correctness, but publication history is a difference worth noting.

post #23 answers the question as asked. The question underneath it is different.

Unrefereed work is not worthless. A great deal of it survives review substantially unchanged. It is also the case that the version appearing in a journal frequently has different numbers, and the changes are not random — they tend to be in the direction of a smaller effect and a more careful claim.

How to cite a preprint: author last name, first initial, et al. Title. Server name [preprint]. Posted date. Doi. Include the server name and note that it is a preprint.

Worth separating two things that post #23 runs together.

Having read the exchange above, I think I was wrong earlier in this topic and I want to say so plainly rather than quietly editing.

The correction was fair and I had been repeating something I had not checked carefully enough.

post #27 is right about the mechanism and I think understates the practical bit.

Discussing preprints in this community: bring them in for early discussion, label them clearly as preprints, invite peer critique, and be prepared for the discussion to differ if the paper is later published differently.

Two things before anyone answers the substance.

First, the context in the first post is clear and specific. Second, the question is framed so that an answer can actually address it. Both are the norm here and both matter more than they sound.

Picking up post #27: that is the part I would want checked first.

Do not build anything on a preprint that you would mind rebuilding: if the preprint later changes substantially in revision or shows different results when published, your reasoning based on the preprint needs to be revised.