Funding for this research was provided by:
National Institute for Health Research (15/01/19)
Medical Research Council Canada (MC_UU_12015/7)
Received: 26 November 2018
Accepted: 25 January 2019
First Online: 9 February 2019
Ethics approval and consent to participate
: All participants provided their written informed consent/assent. This study received ethical approval from the Ethics Committee for the School of the Humanities and Social Sciences at the University of Cambridge.
: Not applicable.
: The authors declare that they have no competing interest. The views expressed are those of the authors and not necessarily those of the NHS, the NIHR, or the Department of Health and Social Care.
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