Using the Newcomb–Benford law to study the association between a country’s COVID-19 reporting accuracy and its development

Abstract

The COVID-19 pandemic has spurred controversies related to whether countries manipulate reported data for political gains. We study the association between accuracy of reported COVID-19 data and developmental indicators. We use the Newcomb–Benford law (NBL) to gauge data accuracy. We run an OLS regression of an index constructed from developmental indicators (democracy level, gross domestic product per capita, healthcare expenditures, and universal healthcare coverage) on goodness-of-fit measures to the NBL. We find that countries with higher values of the developmental index are less likely to deviate from the Newcomb-Benford law. The relationship holds for the cumulative number of reported deaths and total cases but is more pronounced for the death toll. The findings are robust for second-digit tests and for a sub-sample of countries with regional data. The NBL provides a first screening for potential data manipulation during pandemics. Our study indicates that data from autocratic regimes and less developed countries should be treated with more caution. The paper further highlights the importance of independent surveillance data verification projects.

Applying Benford’s law to COVID-19 data: the case of the European Union

“…14–16 More recent studies have used Benford’s law to investigate whether COVID-19 data provided by countries are accurate, 5 , 10 , 11 , 17 and if the deviation from Benford’s distribution could be affected by developmental indexes. 13 Conformity with Benford’s distribution is expected when the data under consideration spread over several terms of magnitude; however, for countries with limited cases and/or deaths, the distribution of the first digit would generally deviate from Benford’s.…”

“…More specifically, countries with higher values of economic indicators, such as GDP and health expenditures, were less likely to deviate from Benford’s law. 13 …”

“… 11 Furthermore, it was found that countries with higher values of the developmental indexes are less likely to deviate from Benford’s law. 13 …”

COVID-19 in Central Asia: exploring the relationship between governance and non-pharmaceutical intervention

“…But are these data reliable? We tested them using Benford’s law ( Benford, 1938 ), as suggested with regard to COVID-19 cases by Sambridge and Jackson (2020) and Balashov et al . (2021) .…”

“…Following Mosimann et al . (1995) and Diekmann (2007) , we run our test on the second digit, in the exponential-growth phase of COVID-19 (as suggested by Balashov et al. , 2021 ) where the number of total cases is expected to be in accordance with the Benford’s Law.…”