Pick S, Anderson DG, Asadi-Pooya AA, Aybek S, Baslet G, Bloem BR, Bradley-Westguard A, Brown RJ, Carson AJ, Chalder T, Damianova M, David AS, Edwards MJ, Epstein SA, Espay AJ, Garcin B, Goldstein LH, Hallett M, Jankovic J, Joyce EM, Kanaan RA, Keynejad RC, Kozlowska K, LaFaver K, LaFrance WC Jr, Lang AE, Lehn A, Lidstone S, Maurer CW, Mildon B, Morgante F, Myers L, Nicholson C, Nielsen G, Perez DL, Popkirov S, Reuber M, Rommelfanger KS, Schwingenshuh P, Serranova T, Shotbolt P, Stebbins GT, Stone J, Tijssen MA, Tinazzi M, and Nicholson TR
Objectives: We aimed to identify existing outcome measures for functional neurological disorder (FND), to inform the development of recommendations and to guide future research on FND outcomes., Methods: A systematic review was conducted to identify existing FND-specific outcome measures and the most common measurement domains and measures in previous treatment studies. Searches of Embase, MEDLINE and PsycINFO were conducted between January 1965 and June 2019. The findings were discussed during two international meetings of the FND-Core Outcome Measures group., Results: Five FND-specific measures were identified-three clinician-rated and two patient-rated-but their measurement properties have not been rigorously evaluated. No single measure was identified for use across the range of FND symptoms in adults. Across randomised controlled trials (k=40) and observational treatment studies (k=40), outcome measures most often assessed core FND symptom change. Other domains measured commonly were additional physical and psychological symptoms, life impact (ie, quality of life, disability and general functioning) and health economics/cost-utility (eg, healthcare resource use and quality-adjusted life years)., Conclusions: There are few well-validated FND-specific outcome measures. Thus, at present, we recommend that existing outcome measures, known to be reliable, valid and responsive in FND or closely related populations, are used to capture key outcome domains. Increased consistency in outcome measurement will facilitate comparison of treatment effects across FND symptom types and treatment modalities. Future work needs to more rigorously validate outcome measures used in this population., Competing Interests: Competing interests: AAA-P reports honoraria from Cobel Daruo, Sanofi and RaymandRad, and royalty from Oxford University Press (book publication). AJC reports independent expert testimony work for personal injury and medical negligence claims, is a paid associate editor of JNNP and runs a free non-profit self-help website (www.headinjurysymptoms.org). AJE has received personal compensation as a consultant/scientific advisory board member for Abbvie, Adamas, Acadia, Acorda, Neuroderm, Impax/Amneal, Sunovion, Lundbeck, Osmotica Pharmaceutical and US WorldMeds; publishing royalties from Lippincott Williams & Wilkins, Cambridge University Press and Springer; and honoraria from US WorldMeds, Lundbeck, Acadia, Sunovion, the American Academy of Neurology and the Movement Disorders Society. BM has received honoraria from The Cleveland Clinic and runs a free non-profit self-help website (www.fndhope.org). WCLF has served on the editorial boards of Epilepsia, Epilepsy & Behavior; Journal of Neurology, Neurosurgery and Psychiatry and Journal of Neuropsychiatry and Clinical Neurosciences; receives editor’s royalties from the publication of Gates and Rowan’s Nonepileptic Seizures, 3rd ed. (Cambridge University Press, 2010) and 4th ed. (2018); author’s royalties for Taking Control of Your Seizures: Workbook and Therapist Guide (Oxford University Press, 2015); has received research support from the Department of Defense (DoD W81XWH-17-0169), National Institutes of Health (NIH) (NINDS 5K23NS45902 [PI]), Providence VAMC, Center for Neurorestoration and Neurorehabilitation, Rhode Island Hospital, the American Epilepsy Society (AES), the Epilepsy Foundation (EF), Brown University and the Siravo Foundation; serves on the Epilepsy Foundation New England Professional Advisory Board; received honoraria for the American Academy of Neurology Meeting Annual Course; served as a clinic development consultant at University of Colorado Denver, Cleveland Clinic, Spectrum Health, Emory University and Oregon Health Sciences University; and provided medicolegal expert testimony. DLP has received honoraria from the American Academy of Neurology, Movement Disorder Society and Harvard Medical School. JS reports independent expert testimony work for personal injury and medical negligence claims, receives royalties from UpToDate for articles on functional neurological disorder and runs a free non-profit self-help website (www.neurosymptoms.org). KLF has received honoraria from the American Academy of Neurology and the Movement Disorder Society. MH may accrue revenue on a US patent for an Immunotoxin (MAB-Ricin) for the treatment of focal movement disorders and for a coil for magnetic stimulation and methods for using the same (H-coil); in relation to the latter, he has received licence fee payments from the NIH (from Brainsway). He is on the medical advisory boards of CALA Health, Brainsway and Cadent. He is on the editorial board of approximately 15 journals and receives royalties and/or honoraria from publishing from Cambridge University Press, Oxford University Press, Springer and Elsevier. Grant research funds have come from Merz for treatment studies of focal hand dystonia; Allergan for studies of methods to inject botulinum toxins; Medtronic, Inc. for a study of DBS for dystonia; and CALA Health for studies of a device to suppress tremor. MJE reports independent expert testimony work for personal injury and medical negligence claims and receives royalties from the Oxford Specialist Handbook of Parkinson’s Disease and Other Movement Disorders. He has received honoraria from Merz Pharma and Boeringher Ingleheim. AEL reports consultancy support from Abbvie, AFFiRis, Biogen, Janssen, Lilly, Lundbeck, Merck, Paladin, Roche, Sun Pharma, Theravance, and Corticobasal Degeneration Solutions; advisory board support form Jazz Pharma, PhotoPharmics, Sunovion; other honoraria from Sun Pharma, AbbVie, Sunovion, American Academy of Neurology and the International Parkinson and Movement Disorder Society; grants from Brain Canada, Canadian Institutes of Health Research, Corticobasal Degeneration Solutions, Edmond J Safra Philanthropic Foundation, Michael J. Fox Foundation, the Ontario Brain Institute, Parkinson Foundation, Parkinson Canada, and W. Garfield Weston Foundation and royalties from Elsevier, Saunders, Wiley-Blackwell, Johns Hopkins Press, and Cambridge University Press., (© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)