Article History
Received: 27 March 2018
Accepted: 20 November 2018
First Online: 12 December 2018
Ethics approval and consent to participate
: The DEGS1 was approved by the Federal and State Commissioners for Data Protection and the Charité-Universitätsmedizin Berlin Ethics Committee (No. EA2/047/08). All participants provided informed written consent. The GNHIES98 was approved by the Board of the Federal Commissioner for Data Protection Berlin.
: Not applicable.
: The authors declare that they have no competing interests.
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