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Improving CDC Data Practices Recommendations for Improving the United States Centers for Disease Control (CDC) Data Practices for Pneumonia, Influenza, and COVID-19 (v 1.1)
  • John F. McGowan, Ph.D.,
  • Tam Hunt,
  • Josh Mitteldorf, PhD
John F. McGowan, Ph.D.

Corresponding Author:[email protected]

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Josh Mitteldorf, PhD
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During the pandemic, millions of Americans have become acquainted with the CDC because its reports and the data it collects affect their day-today lives. But the methodology used and even some of the data collected by CDC remain opaque to the public and even to epidemiologists. In this paper, we highlight areas in which CDC methodology might be improved and where greater transparency could lead to broad collaboration. (1) "Excess" deaths are routinely reported, but not "years of life lost", an easily-computed and more granular datum that is important for public policy. (2) What counts as an "excess death"? The method for computing the number of excess deaths does not include error bars and we show a substantial range of estimates is possible. (3) Pneumonia and influenza death data on different CDC pages is grossly contradictory. (4) The methodology for computing influenza deaths is not described in sufficient detail that an outside analyst might pursue the source of the discrepancy. (5) Guidelines for filling out death certificates have changed during the COVID-19 pandemic, preventing the comparison of 2020-21 death profiles with any previous year. We conclude with a series of explicit recommendations for greater consistency and transparency, and ultimately to make CDC data more useful to the public and epidemiologists and other scientists.