# I found BL\_AGE after FU\_END\_AGE in the endpoint data, how is it possible?

This can happen when an individual gives biobank sample after register follow-up ends. For example, if FU\_END\_DATE is 11.10.2021 (DF9), and individual gives sample to biobank in year 2022, then the BL\_AGE is currently after FU\_END\_AGE.

Other case when this can happen is if an individual has moved abroad (in this case FU\_END\_AGE is age at emigration), but moved back later and gave a sample to biobank. In this case BL\_AGE is after the FU\_END\_AGE and difference can be several years.

Take a look also at the section [Complete follow-up time of the FinnGen registries – primary endpoint data](/finngen-data-specifics/endpoints/complete-follow-up-time-of-the-finngen-registries-primary-endpoint-data.md)


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