Pharmaceutical industry-authored preprints: scientific and social media impact

Non-peer-reviewed manuscripts posted as preprints can be cited in peer-reviewed articles, which has both merits and demerits. International Committee of Medical Journal Editors guidelines mandate authors to declare preprints at the time of manuscript submission. We evaluated the trends in pharma-authored research published as preprints and their scientific and social media impact by analyzing citation rates and altmetrics.

We searched EuroPMC, PrePubMed bioRxiv and medRxiv for preprints submitted by authors affiliated with the top 50 pharmaceutical companies from inception until 15 June 2020. Data were extracted and analyzed from the search results. The number of citations for the preprint and peer-reviewed versions (if available) were compiled using the Publish or Perish software (version 1.7). Altmetric score was calculated using the "Altmetric it" online tool. Statistical significance was analyzed by Wilcoxon rank-sum test.

A total of 498 preprints were identified across bioRxiv (83%), PeerJ (5%), F1000Research (6%), Nature Precedings (3%), Preprint.org (3%), Wellcome Open Research preprint (0.2%) and medRxiv (0.2%) servers. Roche, Sanofi and Novartis contributed 56% of the retrieved preprints. The median number of citations for the included preprints was 0 (IQR = 1, Min-Max = 0-45). The median number of citations for the published preprints and unpublished preprints was 0 for both (IQR = 1, Min-Max = 0-25 and IQR = 1, Min-Max = 0-45, respectively; p = .091). The median Altmetric score of the preprints was 4 (IQR = 10.5, Min-Max = 0-160).

Pharma-authored research is being increasingly published as preprints and is also being cited in other peer-reviewed publications and discussed in social media.