Funding for this research was provided by:
Ministry of Cultural Affairs of the Federal State of Mecklenburg-West Pomerania
Bundesministerium für Bildung und Forschung (01ZZ9603, 01ZZ0103, and 01ZZ0403)
Social Ministry of the Federal State of Mecklenburg-West Pomerania
Received: 23 July 2018
Accepted: 9 January 2019
First Online: 12 February 2019
Ethics approval and consent to participate
: All SHIP and SHIP-Trend participants gave written informed consent. Both studies follow the recommendations of the Declaration of Helsinki and were approved by the ethics committee of the University of Greifswald. In addition, both studies were reviewed by an external scientific review board.
: Not applicable.
: The authors declare that they have no competing interests.
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