The COVID-19 pandemic has exposed so many flaws in global and local public health systems that it’s almost impossible to track them all. From unequal access to vaccines to the overallquality of care available to patients, any belief that we are ready for the next pandemic shattered during the early days of March 2020 as SARS-CoV-2 swept across the globe. Something as basic as keeping track of COVID-19 fatalities ended up being a monumental task even the most technologically advanced nations struggled to carry out. A recent paper in the Journal of the American Medical Association attempted to extrapolate a clearer picture by statistical means.

The researchers compared reported COVID-19 confirmed mortality (CCM) against excess mortality (EM). CCM is considered an unreliable indicator of COVID-19 deaths mostly due to differences between national health care systems and their ability to correctly identify COVID-19 mortalities. 

On the other hand, EM is considered more comprehensive and robust since it relies on all-cause mortality instead of specific causes of death. 

The researchers “retrieved aggregated country-level data on population and COVID-19 overall confirmed cases, deaths, and testing as of December 31, 2020, from OurWorld in Data. Data on countries’ overall deaths from 2015 to 2020 were obtained from the World Mortality Data set.”

By analyzing the differences between the EM and CCM in 67 countries the reseaerchers hoped to get a better picture of whether the official COVID-19 data can be considered reliable.

The researchers found that the greatest discrepancies occurred according to a distinct pattern. 

“The lowest figures of EM and CCM generally belonged to countries with higher testing capacity (in green) and the largest differences between EM and CCM to countries with poorer testing capacity (in red).”

The findings of Sanmarchi et al. are consistent with the findings of similar attempts at finding the true number of COVID-19 fatalities. The authors conclude, “our findings corroborate the evidence that in many countries the accuracy in quantifying the death toll of COVID-19 is still a missed target. The global action against the pandemic is being conditioned by diverse responses to the crisis, but reliable evidence should be the pillar on which effective prevention measures are built.”

The paper “Exploring the Gap Between Excess Mortality and COVID-19 Deaths in 67 Countries” can be read in JAMA Open in its entirety.