Adjustment method to ensure comparability between populations reporting mortality data in different formats in the EURO-GBD-SE project : Working document

Introduction: In some of the longitudinal data sets within the EURO-GBD-SE project, information on age isonly available at baseline, all person years and deaths are attributed to the baseline age; thismeans that information about age at death is unavailable. This will cause a bias whencomparing mortality between data sets in which age at death is reported and data sets in whichage at baseline is reported. Mortality estimates in populations that have age at baseline will behigher than the estimations obtained where age at death is known; since people are notallowed to move into the next age category as they grow older, the population will, in reality,be older in the former case. The data sets that are formatted with age at baseline only areBrussels, Denmark, Finland, Norway, Sweden and Switzerland.To make results comparable, we developed an adjustment procedure that corrects for this bias.This procedure should be applied to the datasets formatted with the age at baseline and is represented in this document