Table 3.

Completeness–inclusion rate of primary studies in each COVID-19 collection

Collection	Records in scope	Records found
		N	%
Epistemonikos	440	410	93.2
WHO	440	405	92.0
LitCovid	440	399	90.7
PubMed	440	385	87.5
SOLES	440	367	83.4
Cochrane COVID-19 study register	407	358	88.0

Four publications were not found in any of the collections.