Footnotes

• Contributors According to the definition given by the International Committee of Medical Journal Editors (ICMJE), the following individuals qualify for authorship based on their substantial contributions to the manuscript’s intellectual content: TH, conception and design; CN and TH, acquisition of data; CN and TH, patient management and interpretation of data. Furthermore, CN and TH have participated in writing the manuscript. All authors have read and approved 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 None declared.

• Patient and public involvement Patients and/or the public were involved in the design, or conduct, or reporting, or dissemination plans of this research. Refer to the Methods section for further details.

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