  Aggregated health data such as claims data from health insurances become more
and more available for research purposes. Estimates of excess mortality from
prevalence and incidence of a chronic condition have only been possible for
ages 50 years and older and have shown to be unstable in younger ages. The aim
of this article is to explore the reasons why estimates of excess mortality for
younger ages are prone to bias and what can be done to extend the age range to
ages below 50 years.
