Funding for this research was provided by:
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (FN 32-57098.99, 3200B0-100657, 320000-113936 and 310030-127064)
Bundesamt für Gesundheit (National Reference Center: 2009/10 (Projekt (911) 316, and 2011/13 (11.006911/304.0001-707))
Text and Data Mining valid from 2018-05-08
Received: 9 March 2018
Accepted: 26 April 2018
First Online: 8 May 2018
Ethics approval and consent to participate
: Not applicable.
: The authors declare that they have no competing interests.
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