Footnotes

• Correction notice This article has been corrected since it published Online First. The provenance and peer review statement has been included.

• Contributors Both authors wrote 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 RCS has received research grants from Ironwood Pharmaceuticals, Zespri International and Sanofi-Aventis and lecturing fees from Menarini and Alfawasserman.

• 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 Commissioned; internally peer reviewed.