In retrospective epidemiological cohort studies the mortality rate of a cohort exposed to certain agents under investigation is compared to the mortality rate of the general population. In Germany, vital status of the cohort is followed up via local population registries. Cause of death of deceased members of the cohort is obtained from death certificates by local health authorities. Since storage time for death certificates is short in some Federal German states, causes of death cannot be obtained if death occurred before storage deadline. Recently it became possible to obtain the cause of death from regional statistical offices. Initial co-operation has been established with the statistical offices of North Rhine Westphalia and Berlin. For a cohort study in the chemical industry, the initially low proportion of causes of death obtained from local health authorities (44.8 %) was increased by 30 % to 74.0 % after obtaining ICD coded causes of death from two regional statistical offices. Further advantages of this new data source are reduction in duration of inquiry time and of overall cost.