Footnotes

• Contributors AR, RM, SC, AA, AF, MS, TR and PC designed the study. TR and AR drafted the manuscript. All authors participated in the data collection and revised and approved the final manuscript.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Patient consent for publication Not required.

• Provenance and peer review Not commissioned; internally peer reviewed.