Characteristics of research publishing, and registered clinical trials on the COVID-19 pandemic focus on japan

Objectives: The academic output of COVID-19 research has been proliferating. I aim to describe the characteristics of the current status of academic information distribution from journal articles and preprints and registries.

Methods: The data sources were PubMed, medRxiv and bioRxiv, the iSearch, ICTRP, PROSPERO from 09/01/2019 to 12/31/2020.No limitations were placed on study design and language. I screened and categorized studies according to i) publication type, ii) Research area, and iii) topics covered.

Results: Over 50,000 articles related COVID-19 were published
until 11 Jan.2021 in PubMed. up 20% between Jun to Dec when compared with the same period in latest 3 years(2017-2019) average. The highest rate of increase was in September, at 31.4 %.
Around 6% of those indexed in PubMed with MeSH or SCPs were dedicated to covid-19 topics. Ichushi-web showed an increase in reports about COVID-19 in September and October 2019. More than 12,000 of the COVID-19 articles published in 2020 were preprints(medRxiv and bioRxiv). Abou 54% of COVID-19-related protocols registerd in ICTRP ware via Clinicalrials.gov, which together with Indis's CTRI(10.7%) and China7s ChiCTR(10.5%), the second and third most popular protocols, accounted for 3/4 of the total.

Conclusions: PubMed differed in the rate of MeSH and SCPs assigned for specific journals. It may be necessary to take this into account when searching for literature related to COVID-19 in order to develop a search strategy. The speed of indexing in PubMed is increasing. Ichushi-Web was a time lag of about half a month and an overwhelming difference in the number of articles compared to PubMed. Cases reports in Japan began when the Infectious Diseases Society of Japan began publishing information related to the acceptance of passengers and cruisers aboard the Diamond Princess on its website. These were later published in a special issue of the Journal of The Japanese Association for Infectious Diseases and reported as papers. However, the fact that such information disclosure and sharing was attempted in Japan from an early stage, including cases that did not published, may have provided valuable information to medical personnel who treated patients in the field. Similarly, the Japanese Respiratory Society and the Japanese Pediatric Society are also attempting to share cases. When searching for information from Japan, it is necessary to check not only literature databases but also these academic society sites and guideline sites.