Footnotes

• Twitter @manjit_matharu, @@spiraldance1

• Contributors EJH and JCR were primarily responsible for study concept and design. JCR was responsible for review of literature and primary writing and preparation of the manuscript. MK provided substantial review and editing of manuscript. MM, LB, RJS and S-JW all provided additional expertise in review, editing and input into manuscript content.

• 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 MM serves on the advisory board for Allergan, Novartis, Eli Lilly, Autonomic Technologies and TEVA and has received payment for the development of educational presentations from Allergan, electroCore, Eli Lilly, Novartis and TEVA. RJS has been a member of Advisory Boards for Allergan, Novartis, Teva and Eli Lilly and has received Lecture Fees from Allergan, Novartis, Teva and Eli Lilly and Biogen. EJH has served on advisory boards for Sanofi-Genzyme, Novartis, Teva, Eli Lilly, Allergan, been involved in clinical trials sponsored by Novartis and Teva, and has received payment for educational presentations from Allergan, Teva, Eli Lilly and Novartis. S-JW has served on the advisory boards of Eli Lilly, Daiichi-Sankyo and Taiwan Norvatis. He has received honoraria as a moderator from Allergan, Pfizer, Eli Lilly, Bayer, and Eisai. He has received research grants from the Taiwan Minister of Technology and Science, Brain Research Center, National Yang-Ming University from The Featured Areas Research Center Programme within the framework of the Higher Education Sprout Project by the Ministry of Education (MOE) in Taiwan, Taipei Veterans General Hospital, and Taiwan Headache Society. LB serves on the advisory board for Allergan, Novartis, Eli Lilly and Teva, has been involved in clinical trials sponsored by Novartis and has received payment for educational presentations from Allergan, Teva and Novartis. JR and MK report no potential conflict of interest. Figure created with biorender.com.

• Patient consent for publication Not required.

• 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.