
Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Supplemental material This content has been supplied by the author(s). Provenance and peer review Not commissioned externally peer reviewed.


JPGdC, RG, FS, FNA, BSM, BBC, JMS, ECB and JRF approved the final version to be published.įunding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors. JPGdC, RG, FS, FNA, BSM, BBC, JMS, ECB and JRF critically reviewed the article. JPGdC, RG, FS, FNA, BSM, BBC, JMS, ECB and JRF participated in the data analysis and interpretation. JPGdC, RG, FNA and BBC participated in the data collection.

