Estimation of total mortality due to COVID-19
This isn&#x27;t a &quot;study&quot;, it&#x27;s a statistical model. It reflects the assumptions put into it. To wit:<p>&gt; Our analysis follows four key steps. First, for all locations where weekly or monthly all-cause mortality has been reported since the start of the pandemic, we estimate how much mortality increased compared to the expected death rate....Second, based on a range of studies and consideration of other evidence, we estimate the fraction of excess mortality that is from total COVID-19 deaths as opposed to the five other drivers that influence excess mortality. Third, we build a statistical model that predicts the weekly ratio of total COVID-19 deaths to reported COVID-19 deaths based on covariates and spatial effects. Fourth, we use this statistical relationship to predict the ratio of total to reported COVID-19 deaths in places without data on total COVID-19 deaths and then multiply the reported COVID-19 deaths by this ratio to generate estimates of total COVID-19 deaths for all locations.<p>And, what, you may ask, are the biases of the models&#x27; authors with regards to the percentage of excess mortality due to Covid itself? Excellent question:<p>&gt; Deaths that are directly due to COVID-19 are likely underreported in many locations, particularly in settings where COVID-19 testing is in short supply. <i>Most excess mortality is likely misclassified COVID-19 deaths.</i><p>&gt; Given that there is insufficient evidence to estimate these contributions to excess mortality, <i>for now we assume that total COVID-19 deaths equal excess mortality.</i> For the reasons presented in this section, we believe that this is likely an underestimate.<p>As someone who has now spent the better part of his life creating statistical models, <i>when you assume something is true, your model is likely to confirm your assumptions.</i><p>This is why statistical models are worthless without prospective validation. If you haven&#x27;t shown that your assumptions are correct for the <i>future</i>, you&#x27;re just making castles in the sky.