Up to 1 in 3 death certificates nationwide were already wrong before COVID-19, said Bob Anderson, chief of the mortality statistics branch at the National Center for Health Statistics in an interview with the USA TODAY Network.

"I'm always worried about getting good data. I think this sort of thing can be an issue even in a pandemic," Anderson said.

Experts say the inaccuracies are part and parcel of a patchwork, state-by-state system of medical examiners, coroners and doctors who have disparate medical backgrounds, and in some cases none at all.
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A 2017 review of Missouri hospitals, for example, found nearly half of death certificates listed an incorrect cause of death. A Vermont study found 51% of death certificates had major errors. Nearly half of the physicians the Centers for Disease Control and Prevention surveyed in 2010 admitted that they knowingly reported an inaccurate cause of death.
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Despite this, Anderson said, some physicians will simply list the cause of death as pneumonia when the pneumonia likely came after a COVID-19 infection. But he hopes fewer do.