Monitoring trends and differences in COVID-19 case fatality rates using decomposition methods: Contributions of age structure and age-specific fatality

Christian Dudel; Tim Riffe; Enrique Acosta; Alyson A. van Raalte; Mikko Myrskyla

Finally, the choice of age groups may have affected our results. If ages were grouped too widely it might hide actual age-specific case fatality differences. For instance, if the median age within the 10-year aggregated age groups that we used differed between populations, this would reduce the case-age structure explanation and inflate the age-specific mortality explanation. Finally, there are alternative decomposition techniques that might yield different results. However, differences are expected to be rather small; indeed, applying the method of Horiuchi [24] to our data yields virtually the same results (results available upon request).