@article{c8847fa4d29f475393e9390cea3d8bf6,
title = "Development and Validation of the Orthostatic Tremor Severity and Disability Scale (OT-10)",
abstract = "Background: Limited tools are available for the assessment of orthostatic tremor severity and disability. Objectives: To develop and validate a self-administered orthostatic tremor scale. Methods: After expert consensus and literature review generating a list of 42 items, the scale was developed and modified for validation after a patient focus group, multiple rounds of Delphi panels, and cognitive interviews. Clinimetric evaluations included assessing content validity, internal consistency, measurement error and reliability, construct validity, and concurrent validity anchored on the examiner's Clinical Global Impression score. Results: Eleven items ranked on a Likert scale from 0 (no disability/severity) to 5 (maximal disability/severity) were evaluated in 54 orthostatic tremor patients (16 men and 38 women; mean age: 69.17 ± 9.64 years; disease duration: 13.83 ± 11.24 years) to probe severity and disability over the preceding 1-week period. The 11-item scale showed good internal consistency (Cronbach's alpha = 0.863) and acceptable (>0.40) item-to-total correlation. However, one item was removed at the final Delphi panel because of significant floor effect, poor item-to-total correlation, and poor factor-loading, leaving the scale with 10 items (10-item Orthostatic Tremor Severity and Disability Scale). Test-retest reliability at 2 weeks was excellent (two-way random intraclass correlation coefficient > 0.90), and the individual item test-retest reliability showed good agreement, with a threshold weighted kappa >0.60 for all items. Exploratory factor analyses revealed a parsimonious two-factor construct accounting for 57.7% of the scale's variance. The 10-item Orthostatic Tremor Severity and Disability Scale scores correlated with the CGI. Conclusions: The self-administered 10-item Orthostatic Tremor Severity and Disability Scale scale is valid and reliable for capturing orthostatic tremor–related severity and disability.",
keywords = "clinimetrics, disability, orthostatic tremor, scale, severity",
author = "Aristide Merola and Torres-Russotto, {Diego R.} and Stebbins, {Glenn T.} and Vizcarra, {Joaquin A.} and Shukla, {Aparna Wagle} and Anhar Hassan and Luca Marsili and Krauss, {Joachim K.} and Elble, {Rodger J.} and G{\"u}nther Deuschl and Espay, {Alberto J.}",
note = "Funding Information: Dr. Merola has received grant support from the National Institutes of Health (NIH; KL2 TR001426). He has received speaker honoraria or advisory board honoraria from CSL Behring, AbbVie, Abbott, Medtronic, Theravance, and Cynapsus Therapeutics. He has received grant support from Lundbeck and AbbVie. Dr. Torres‐Russotto has received honoraria from AbbVie, Acadia, Acorda, Adamas, Allergan, Global Kinetic Corporation, Ipsen, Kyowa Kirin, Lundbeck, Sunovion, and Teva. Prof. Stebbins has received advisory board honoraria from Acadia, Pharmaceuticals, Adamas Pharmaceuticals, Inc., Biogen, Inc., Ceregene, Inc., CHDI Management, Inc., Cleveland Clinic Foundation, Ingenix Pharmaceutical Services (i3 Research), MedGenesis Therapeutix, Inc., Neurocrine Biosciences, Inc., Pfizer, Inc., Tools‐4‐Patients, Ultragenyx, Inc., and Sunshine Care Foundation; grants from the NIH, Department of Defense, Michael J. Fox Foundation for Parkinson's Research, Dystonia Coalition, CHDI, Cleveland Clinic Foundation, International Parkinson and Movement Disorder Society, and CBD Solutions; honoraria from the International Parkinson and Movement Disorder Society, American Academy of Neurology, Michael J. Fox Foundation for Parkinson's Research, U.S. Food and Drug Administration, NIH, and the Alzheimer's Association. Dr. Wagle Shukla has received grant support from the Benign Essential Blepharospasm Research Foundation, Dystonia Coalition, Dystonia Medical Research Foundation, National Organization for Rare Disorders, and NIH (KL2 and K23 NS092957‐01A1); has received honoraria from Acadia, Cavion, Elsevier, and the Michael J. Fox Foundation for Parkinson's Research in the past; and participates as a co‐investigator for several NIH‐, foundation‐, and industry‐sponsored trials over the years, but has not received honoraria. Dr. Hassan has received research support from Intrabio and honoraria from the American Academy of Neurology. Dr. Krauss is a consultant to Medtronic and Boston Scientific; received honoraria from AbbVie and Baxter; and received publishing royalties from Kohlhammer Verlag and Cambridge University Press. Dr. Elble has received consulting fees from Cadent, Cavion, Cydan, Jazz, Osmotica, and Praxis Prcision Medicines. He receives research funds from the Kiwanis Neuroscience Research Foundation, Illinois‐Eastern Iowa District, and he has received honoraria from the International Parkinson and Movement Disorder Society. Dr. Deuschl received personal fees from Boston Scientific, Cavion, Functional Neuromodulation, and Thieme publishers and grants from Medtronic, outside the submitted work. He receives funding for his research from the German Research Council (SFB 1261, B5). Dr. Espay has received grant support from the NIH, Great Lakes Neurotechnologies, and the Michael J. Fox Foundation; personal compensation as a consultant/scientific advisory board member for AbbVie, TEVA, Impax, Acadia, Acorda, Cynapsus/Sunovion, Lundbeck, Intrance, and USWorldMeds; publishing royalties from Lippincott Williams & Wilkins, Cambridge University Press, and Springer; and honoraria from AbbVie, UCB, USWorldMeds, Lundbeck, Acadia, the American Academy of Neurology, and the International Parkinson and Movement Disorder Society. Publisher Copyright: {\textcopyright} 2020 International Parkinson and Movement Disorder Society",
year = "2020",
month = oct,
day = "1",
doi = "10.1002/mds.28142",
language = "English (US)",
volume = "35",
pages = "1796--1801",
journal = "Movement Disorders",
issn = "0885-3185",
publisher = "John Wiley and Sons Inc.",
number = "10",
}