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Covid-19 changes the face of preprints

Pandemic preprints are shorter and faster, and make up a quarter of Covid-19 related science

The importance of pre-print papers to the research world has been laid bare by a study showing that they account for a quarter of all publications related to Covid-19.

The pandemic has also changed academic communication, said the study authors, with pre-prints on Covid-19 being accessed, shared and cited more than non-Covid research. The authors also said they are shorter and take less time to be published in traditional journals.

“Taken together, our data demonstrate the importance of rapidly and openly sharing science in the context of a global pandemic and the essential role of preprints in this endeavour,” wrote the paper’s lead author Nicholas Fraser, a researcher at the Leibniz Information Centre for Economics in Germany, and his colleagues.

Recent years have seen a surge of interest in preprints—research papers uploaded by authors to servers and published without the formal peer review that comes with traditional journals. Many preprints go on to be published in journals, but many do not.

For their paper in Plos Biology on 2 April, Fraser’s team analysed preprints published within 10 months of the first confirmed Covid-19 case on two popular servers for biomedical research, bioRxiv and medRxiv.

Scientists published more than 125,000 Covid-19-related scientific articles in this time, and more than 30,000 of these were accessible on these two preprint servers, which together hosted almost 25 per cent of Covid-19-related science.

Covid-19 preprints were an average 32 per cent shorter in length. In the time period studied, 21.1 per cent of Covid-19 preprints were later published in journals, versus 15.4 per cent of non-Covid preprints, and they were published in an average of 68 days versus 116 days.

Fraser found that preprints on Covid-19 were accessed more, cited more and shared more on online platforms than preprints on other subjects.

Social impact


Such papers “pervaded” traditional news outlets and also attracted huge attention on social media, the researchers found.

Coronavirus-related preprints got far greater attention on social media, including Twitter, than other types of preprints. The most ‘tweeted’ non-Covid-19 preprint in the study garnered 1,656 tweets—a paltry sum compared with eight of the top 10 tweeted Covid-19 preprints, which were tweeted over 10,500 times each.

But while this shows that preprints are being widely shared with the public, the authors sounded a cautionary note.

They highlighted that the fourth most tweeted Covid-19 preprint was a widely criticised study linking the coronavirus protein to those found in HIV. The paper was later withdrawn, but not before it had attracted huge attention on social media.

The study authors noted that non-scientific attention to pre-prints is not always welcome, with “one of the primary concerns among authors around posting preprints [being] premature media coverage”.

They noted that both bioRxiv and medRxiv included banners displaying a warning message that preprints should not be seen as conclusive evidence, but that such warnings were often ignored.