Funding for this research was provided by:
Health Research Council of New Zealand (15/496)
University of Otago (Otago Research Grant)
Text and Data Mining valid from 2019-02-08
Received: 16 March 2018
Accepted: 23 January 2019
First Online: 8 February 2019
Ethics approval and consent to participate
: The study was conducted in accordance with the Declaration of Helsinki and received approval from the University of Auckland Human Participants Ethics Committee (reference number 015069). Written informed consent was obtained from all participants before they commenced the study.
: Not applicable
: The corresponding author RM is a member of the Editorial Authors for BMC Public Health; he has no other financial or non-financial competing interests. The remaining authors declare that they have no financial or non-financial competing interests.
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