Refining seasonal mortality estimates through age adjustment: Evidence from Serbia, 2015–2023 (by Ivan Marinković)

Background: Seasonal fluctuations in mortality are a persistent demographic and public health phenomenon. The ideal mortality (IDE) framework estimates seasonal excess mortality by comparing observed outcomes with a counterfactual based on the lowest-mortality seasonal window. Objective: This study evaluates the validity of the IDE framework when applied to age- and sex-specific mortality in Serbia and proposes an age-structure adjustment (IDEadj) to address anomalies in age-specific estimates.