Funding for this research was provided by:
Medical Research Foundation (MR/K023187/1)
Text and Data Mining valid from 2019-01-17
Received: 3 August 2018
Accepted: 3 January 2019
First Online: 17 January 2019
Ethics approval and consent to participate
: Ethics approval for NDNS was obtained from the Oxfordshire Research Ethics Committee. No further ethical approval was required for the secondary analysis of anonymised data which is presented here.
: Not applicable.
: The authors declare that they have no competing interests and no financial disclosures to make.
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