A cross-country database of COVID-19 testing

Abstract

Our understanding of the evolution of the COVID-19 pandemic is built upon data concerning confirmed cases and deaths. This data, however, can only be meaningfully interpreted alongside an accurate understanding of the extent of virus testing in different countries. This new database brings together official data on the extent of PCR testing over time for 94 countries. We provide a time series for the daily number of tests performed, or people tested, together with metadata describing data quality and comparability issues needed for the interpretation of the time series. The database is updated regularly through a combination of automated scraping and manual collection and verification, and is entirely replicable, with sources provided for each observation. In providing accessible cross-country data on testing output, it aims to facilitate the incorporation of this crucial information into epidemiological studies, as well as track a key component of countries' responses to COVID-19.

Fig. 1

COVID-19: Daily tests vs. Daily new confirmed cases, per million Panel A plots the number of daily tests against the number of daily confirmed cases per million of the population, as of August 31. Both are given as the rolling 7-day average. Panel B shows the same two variables over time for five selected countries. All axes are given on a log scale. Note that comparisons of testing data between countries are affected by reporting differences. Details for each country can be found in the metadata. Data on confirmed cases is from the European CDC.

Fig. 2

Number of days between the most recent observation for each country and the date of updating (31 August 2020). Because countries update their testing data at different frequencies, the latest data in the database for each country does not in all cases refer to the date the database was updated.