Quality of early evidence on the pathogenesis, diagnosis, prognosis and treatment of COVID-19.

Since the initial description of the SARS-CoV-2 outbreak and its declaration as a worldwide pandemic, the number of publications on the novel virus has increased rapidly. We studied the trends and quality of evidence in early SARS-CoV-2 publications. A comprehensive search of MEDLINE and EMBASE was performed for papers published between 1 January 2020 and 21 April 2020.