Are a third of the excess deaths this year not linked to COVID-19? Yes. Are they directly linked to the lockdown? It's complicated.

An article published in the Washington Examiner by Michael Lee reports that one-third of excess deaths in U.S. during pandemic could not be directly attributed to the coronavirus. The article accurately sites a study published in the Journal of the American Medical Association which examined the number of excess deaths in the U.S. from 1 March to 1 August 2020, which claimed a 20% increase (+225,530 excess deaths). The study reports that only 67% of deaths were recorded as being directly due to COVID-19, based on the underlying cause of death registered on death certificates. However, there is no scientific evidence that the remaining 33% of deaths were a direct result of lockdown measures. It's worth mentioning that the study published in JAMA has not been peer reviewed. There is also a similar study posted by the U.S. Centers for Disease Control and Prevention which calculates a lower percentage of 14.5% excess deaths not caused by the virus.

As reported by Pablo Rougerie on Health Feedback... 

To calculate excess death, the observed number of deaths over a specific period is compared to an estimate of the expected number of deaths, which is calculated based on deaths from previous years during that same period. An increase in deaths relative to the expected number is an indication of an ongoing lethal event, such as an epidemic.

The JAMA research article compared the number of deaths in the U.S. from 1 March to 1 August 2020 and found a 20% increase in mortality, amounting to 225,530 excess deaths. The authors also observed that only 67% of deaths were recorded as being directly due to COVID-19, based on the underlying cause of death registered on death certificates.

A study from the U.S. Centers for Disease Control and Prevention (CDC) corroborates these results^[2]. The CDC study compared the number of deaths from 26 January to 23 October in 2020 with an expected number of deaths based on the mortality in 2015-2019, and found an excess of 299,028 deaths. Consistent with the JAMA study relayed by the Washington Examiner, the CDC study also noted that one-third of these deaths were not directly attributed to COVID-19, according to the cause of death on death certificates.

However, the CDC study contains one caveat. As explained above, excess mortality is obtained by subtracting two numbers: the observed number of deaths and the expected number of deaths. Therefore, the number of excess deaths calculated depends on how researchers determine the expected number of deaths.

The CDC study calculated the excess deaths using two different methods which provides a range of excess death estimates. The upper estimate was the aforementioned 299,028 excess deaths while the lower estimate fell to 224,173[2].

More importantly, the number of excess deaths that are not attributed to COVID-19 was only 14.5% when using this lower estimate. As the CDC notes, this lower estimate is more conservative as it “more readily identifies areas experiencing statistically significantly higher than normal mortality”.

Therefore, the Washington Examiner’s claim that one-third of excess deaths seen during the pandemic were not due to COVID-19 is based on accurate, published data. However, it does not accurately convey the level of uncertainty involved in the measurement. Depending on how excess death is calculated, the number of excess deaths not attributed to COVID-19 may decrease to less than 15% of the total of excess deaths.

The Washington Examiner also claims that lockdowns are partly responsible for excess deaths observed in 2020 not directly attributed to COVID-19. However, this claim is unsupported by scientific evidence. Instead, both the JAMA and CDC studies list several possible explanations for these excess deaths, notably “unrecognized or undocumented infection with severe acute respiratory syndrome coronavirus 2.” The JAMAstudy also highlights “disruptions in health care access or utilization” as another possible explanation for these excess deaths, however it does not attribute disruption in healthcare access to lockdowns, as the Washington Examiner article does.

Another potentially important contributor to disruption in healthcare services is an overloaded healthcare system as a result of the COVID-19 pandemic, which the Washington Examiner article does not acknowledge.