Footnotes

• Handling editor Josef S Smolen

• Contributors EEG, GM and DS were involved in study conception and design. EEG, GM, AM, GE, MVi, AM, A-CD, ALJ, FD, GL, HB, MVa, PC, SB, DS were involved in the acquisition of data. EEG, GM and DS were involved in the analysis and interpretation of data. EEG, GM and DS assume full responsibility for the veracity and completeness of the reported data. All authors had full access to the data and were involved in drafting the article or revising it critically for important intellectual content, and all authors reviewed and approved the final version of the manuscript to be published.

• 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 not involved in the design, or conduct, or reporting, or dissemination plans of this research.

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

• Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.