Funding for this research was provided by:
Bundesministerium für Bildung und Forschung
Health Research Board
Ministero della Salute
Organization for Health Research and Development
The Swedish Research Council for Health, Working Life and Welfare
The Research Council of Norway
National Foundation for Science and Technology
Economic and Social Research Council
Received: 19 March 2017
Accepted: 14 May 2018
First Online: 4 June 2018
: GM is a member of the BMC Geriatrics editorial board, but was not involved in the review process.
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