The study aims to evaluate global research output (103054 records) on coronavirus disease (COVID-19) based on quantitative and qualitative indicators. It presents a bibliometric profile of most influential countries, organizations, authors and journals and their collaborative linkages, besides identifying broad subject areas of research, most significant keywords and highly-cited papers related to COVID-19. During 2020-21, more than 150 countries participated in COVID-19 research, of which top 10 countries accounted for a 82.93% global share. The USA, China and U.K. produced the most articles (25.86%, 10.77% and 10.7% respectively). The top three organizations, namely Harvard Medical School, USA, Huazhong University of S&T, China and Tongji Medical College, China contributed 1755, 1344 and 1267 papers, respectively. The most cited organizations in COVID-19 research are: Peking Union Medical College, China (97.41 CPP), University of Hong Kong (82.17 CPP) and Renmin Hospital of Wuhan University, China (59.88 CPP). The top three most productive authors are: V. Wanitlit, E. Mahase and G. Lacobucci (with 152, 135 and 108 papers). The top three most cited authors in terms of citations per paper (CPP) are: Y. Hu (319.82), L. Liu (303.91) and J.F.W. Chan (169.55). The most productive organizations originate from most productive countries and they contribute the most collaborative papers. The top three journals, namely International Journal of Environmental Research, BMJ and PLOS One contributed 961, 854 and 781 papers, respectively. The top three journals in terms of citations per paper (CPP) are New England Journal of Medicine (122.78), The Lancet (106.3) and JAMA (75.17). The most ubiquitous topic was COVID-19 clinical studies, with maximum focus on virological aspects (9.58%), respiratory aspects (6.97%), molecular aspects (3.11%), genetic aspects (3.09%) and immunological aspects (1.3%). The results of this study should be of interest to working scientists, clinicians and policy-makers in improving their understanding of COVID-19 disease and in its management.
