Publish or perish: reporting characteristics of peer-reviewed publications, pre-prints and registered studies on the COVID-19 pandemic

Background The COVID-19 pandemic has resulted in a mass of academic papers being published in a very brief span of time. Our aim was to compare the amount and reporting characteristics of COVID-19 related peer-reviewed and pre-prints publications. We also investigated the amount of ongoing trials and systematic reviews. Methods and findings A cross-sectional study of publications covering the COVID-19 pandemic time frame, up to May 20, 2020 was conducted. PubMed with appropriate combinations of Medical Subject Headings and COVID-19 section of MedRxiv and BioRxiv archives were searched. We examined Clinicaltrial.gov, Chinese Clinical Trial Registry, EU Register and 15 other trial registers as well as the international prospective register of systematic reviews (PROSPERO). Characteristics of each publication source were extracted. Regression analyses and Z tests were used to analyze publication trends over the weeks and compare their relative proportions. We found 3635 peer-reviewed publications and 3805 pre-prints, of which 8.6% (n=329) were published in indexed journals. Peer-reviewed and pre-print publications amount both increased significantly over time (p<0.001). Case reports (peer-reviewed: 6% vs pre-prints: 0.9%, p <0.001) and letters (17.4% vs 0.5%, p <0.001) accounted for a greater share of the peer-reviewed compared to pre-print publications. In turn, randomized controlled trials (0.22% vs 0.63% p <0.001) and systematic reviews (0.08% vs 5%) accounted for a significantly greater share of the pre-print publications. Clinicaltrials.gov, Chinese Clinical Trial Registry and EU register included 57.9%, 49.5 % and 98.9% trials mostly still “recruiting”. PROSPERO amounted to 962 systematic review protocols. Conclusion Pre-prints were slightly more prevalent than peer-reviewed publications, yet both are growing. To fill the void given by the absence of published primary studies, immediate opinions (i.e., letters) has virulently been published in PubMed. However, preprints has been promoted as rapid responses to give direct and promptly access at scientific findings in this pandemic.