Number of COVID-related publications in each publication type according to PubMed

The PubMed search was conducted on March 26, 2022, to find out the number of publications in COVID-19 research for each category of publication type defined in PubMed. The PubMed search was conducted using the following search terms:(((COVID[Title/Abstract]) OR (COVID-19[Title/Abstract])) OR (SARS-CoV-2[Title/Abstract])) AND (("2020/01"[Date - Publication] : "2020/11"[Date - Publication])) AND Xa[PT] aX represents one of seventy-nine publication types in PubMed.