Preprints in motion: tracking changes between posting and journal publication

s represent the first port of call for most readers, usually being freely available, brief, relatively 264 jargon-free, and machine-readable. Importantly, abstracts contain the key findings and conclusions 265 from an article. To analyse differences in abstracts between preprint and paper, we employed multiple 266 approaches. We first objectively compared textual changes between abstract pairs using a 267 computational approach before manually annotating abstracts (Fig. 3). Both approaches 268 demonstrated that COVID-19 articles underwent greater textual changes in their abstracts compared 269 to non-COVID-19 articles. However, in determining the type of changes, we discovered that 6% of non270 COVID-related abstracts and 15% of COVID-related abstracts had discrete, “major” changes in their 271 conclusions. Indeed, 42% of non-COVID-19 abstracts underwent no meaningful change between 272 preprint and published versions, though only 34% of COVID-19 abstracts were similarly unchanged. 273 The majority of changes were “minor” textual alterations that lead to a minor change or strengthening 274 or softening of conclusions. Of note, about 1/3 of changes were additions of new data (Fig 3F). While 275 previous works have focused their attention on the automatic processing of many other aspects of 276 . CC-BY 4.0 International license perpetuity. It is made available under a preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in The copyright holder for this this version posted February 20, 2021. ; https://doi.org/10.1101/2021.02.20.432090 doi: bioRxiv preprint