Covid-19 Mortality Rates Adjusted by Differences in Age Structure of Populations

Abstract

One of the tools to monitor the dynamics of the Covid-19 pandemic has been, from its earliest days, the international comparison of mortality rates. The indisputable evidence that lethality is exponentially related to the age of the affected people implies that, for many purposes, a more appropriate indicator should compensate for differences in the age profile between populations. This article sets out a method for calculating such standardized mortality rates, which take into account both the discrepancies in the age pyramids and the mortality rates by age groups. Advancing relatively to the few other similar initiatives found in the literature, the method is applied to a group of 28 countries that on 1/28/2021 accounted for 82% of deaths caused by the pandemic. The age-adjusted mortality rates describe a picture quite different from that portrayed by the crude rates, with three different patterns of mortality. Six Latin American countries and South Africa assume leading positions in the ranking calculated based on these rates. Moreover, a partial but sufficiently accurate update of the calculation based on the number of deaths until 3/26/2021 indicates that in this ranking Brazil only stands behind Mexico and Peru.