TheEconomist/covid-19-the-economist-global-excess-deaths-model

Adjusting for the age profile of a population

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Ted-54 commented

The economist's model does not appear to account for the age profile of a population - unless I have missed something. For instance, in Germany, from 2019 to 2020, the number of 80-90 year olds increased by nearly 264,000, the biggest increase of any age group (some saw reductions), i.e. 5.84% of the total population in 2020 as against 5,53% in 2019. The over 90 year olds increased by 28,000, 0,99% of the total in 2020 as against 0.96% in 2019. Therefore, an increase in deaths in those groups is not in the least surprising and will affect the overall mortality. If not otherwise accounted for, this will show up as excess deaths against an average calculated from years with smaller proportions of 80 + individuals.

sondreus commented

Hi Ted-54,

That would indeed be an oversight, however our models do account for this by modelling expected mortality increases over time. Whenever we have total mortality data for pandemic years, as we do for Germany, it is this modelled expected mortality we compare it to. You can view the code we use to model mortality increases over time here, at the repo this model dynamically pulls excess deaths data from: https://github.com/TheEconomist/covid-19-excess-deaths-tracker

The only exception to this is for our subnational data (from India, and Indonesia), where models are here: https://github.com/TheEconomist/covid-19-the-economist-global-excess-deaths-model/blob/main/scripts/aux_subnational_data_generation.R

And for the three months of data from China, which is detailed in the main data generation script.

Hope this clarifies, and thank you for the comment.

Ted-54 commented
sondreus commented

My pleasure!

Ted-54 commented
Ted-54 commented
sondreus commented

Hi Ted-54,

Thanks for the link. It does account for birth cohort sizes implicitly, by looking at how mortality changes by year for our projections for "normal year" deaths for 2020 and 2021. So unless there was a particular reason to expect a discrete jump from 2019 to 2020 very unlike year-to-year changes from 2014-2019, then the approach incorporates this information.

Ted-54 commented
sondreus commented

Hi Ted-54,

  1. You can view our methodology for a non-academic audience here: https://www.economist.com/graphic-detail/2021/05/13/how-we-estimated-the-true-death-toll-of-the-pandemic -- to read more about underlying excess deaths calculations when we have data on total mortality (most of the time for Germany), you can have a look here: https://www.economist.com/graphic-detail/coronavirus-excess-deaths-tracker
  2. Not entirely sure what you mean here. I would recommend the people at https://www.mortality.org/, who would be able to tell you more about age-specific mortality data (we use total mortality for our models, as few countries have it by age).
  3. I haven't had time to view it unfortunately.

Thanks!