Funding for this research was provided by:
This study was funded by Newcastle University Institute for Ageing.
Received: 28 June 2018
Accepted: 21 December 2018
First Online: 23 January 2019
Ethics approval and consent to participate
: Ethical approval for this study was provided by Newcastle University ethics committee (NO5727). All participants gave written informed consent to take part in the study.
: Not applicable.
: All co-authors are employees of Newcastle University. Otherwise there are no financial relationships with any organisations that might have an interest in the submitted work in the previous three years and no other relationships or activities that could appear to have influenced the submitted work.
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