Footnotes

• Contributors SYK drafted and revised the manuscript for intellectual content, designed and conceptualised the study, analysed and interpreted the data, supervised and coordinated the study and gave final approval of this manuscript; RDV revised the manuscript for intellectual content, designed and conceptualised the study, analysed and interpreted the data, supervised and coordinated the study and gave final approval of this manuscript; RGH revised the manuscript for intellectual content, designed and conceptualised the study, analysed and interpreted the data and gave final approval of this manuscript; KK revised the manuscript for intellectual content, designed and conceptualised the study, analysed and interpreted the data and gave final approval of this manuscript. All authors agree to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

• Funding There was no special funding for the writing of this commentary.

• Disclaimer The opinions in the article are the authors' own and do not represent the views of the NIH, DHHS or the federal government.

• Competing interests KK reports the following financial disclosures. He is a consultant for National Institutes of Health (NINDS), Acorda, Astellas Pharma, AstraZeneca, Auspex, Biotie, Britannia, Cangene, CHDI, Clearpoint Strategy Group, Clintrex, Cynapsus, INC Research, Intec, Isis, Lilly, Lundbeck, Medivation, Melior Discovery, Neuroderm, Neurmedix, Omeros, Otsuka, Pfizer, Pharm2B, Prothena/Neotope/Elan Pharmaceutical, Raptor Pharmaceuticals, Roche/Genentech, Sage Bionetworks, Serina, Stealth Peptides, SynAgile, Teikoku Pharma, Titan, Turing Pharmaceuticals, Upsher-Smith, US WorldMeds, Vaccinex, Voyager, Weston Brain Institute. He received grants/research support from National Institutes of Health (NINDS), Michael J Fox Foundation and Teva. RGH is an Associate Editor of Neurology Today and is a consultant to MCG reviewing neurology guidelines. He also received funding from the NIH.

• Provenance and peer review Commissioned; internally peer reviewed.