Footnotes

• Contributors JYB, SV and RH were involved in manuscript writing and critical revision of the 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 JYB: Consultant for Olympus America Inc. and Boston Scientific Corporation.SV: Consultant for Boston Scientific Corp., Olympus America Inc., Covidien and Creo Medical.RH: Consultant for Boston Scientific Corp., Olympus America Inc., Covidien, Creo Medical, Nine Points Medical and Cook Medical.

• Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

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