With the Covid‐19 pandemic and our limited ability to examine our Parkinson's disease
patients in person, telemedicine and digital visits have become a necessary protective
step to assure high‐quality care and safe distancing. For movement disorder specialists,
our usual reliance on the Movement Disorder Society–Unified Parkinson's Disease Rating
Scale (MDS‐UPDRS) is compromised because rigidity cannot be assessed without touching
the patient, and in most instances, postural reflexes cannot be safely performed without
a trained health professional. As leaders of the MDS‐UPDRS development program, we
have been contacted in the past weeks by many colleagues asking how to record an ongoing
MDS‐UPDRS score in the context of such limitations and how to interpret resultant
scores against prior prospectively collected longitudinal ratings of the same patient.
In this context, we refer to our earlier article
1
published in Movement Disorders on handling missing values in the MDS‐UPDRS. In this
analysis of a large set of full MDS‐UPDRS scores obtained by in‐person neurological
evaluations, we randomly and selectively deleted item scores to establish the number
of missing values that could be tolerated and still allow a highly reliable surrogate
summary score to be calculated for each MDS‐UPDRS part. To summarize our key findings
in the context of how we anticipate that colleagues will be trying to use the MDS‐UPDRS
in the coronavirus disease environment, Part III (motor examination), if applied across
all Hoehn and Yahr stages, can accommodate the consistent loss of only 3 values on
any given visit and still allow the calculation of a calibrated total score that is
valid. In the instance of our typical digital‐based telemedicine visit, 5 rigidity
scores and postural reflexes will be lost, and these 6 missing values fall outside
the permissible threshold. As such, and with reference back to the details of the
full article, we cannot recommend surrogate calculations when rigidity and postural
reflexes cannot be accurately documented.
Furthermore, we emphasize that our publication was based on in‐office examinations,
not video‐based assessments. To our knowledge, there are no publications involving
large samples across all Hoehn and Yahr stages to allow an assessment of the reliability
and validity of video‐based MDS‐UPDRS examinations compared with in‐office visits.
This work, tedious but essential, will provide the defining data set that will potentially
allow clinical and research efforts to move outside the office or hospital base and
take advantage of technologies accessible to all patients.
Given the current situation and the lack of indicators of valid video‐based MDS‐UPDRS
administration, we therefore refer our colleagues to the recommendations from the
US Food and Drug Administration
2
and the European Medicines Agency
3
to be honest, humbly admit to our limitations, do our best, and document what we do.
We are very comfortable providing video‐based or telemedicine care of high quality
and compassion in Parkinson's disease, but at this point, we cannot recommend using
the MDS‐UPDRS scoring imputations that were recommended previously for fieldwork and
other contexts.
Author Roles
(1) Research Project: A. Conception, B. Organization, C. Execution; (2) Statistical
Analysis: A. Design, B. Execution, C. Review and Critique; (3) Manuscript: A. Writing
of the First Draft, B. Review and Critique.
C.G.G.: 1A, 1B, 1C, 2A, 2C, 3A, 3B
G.T.S.: 1A, 1B, 1C, 2A, 2B, 2C, 3B
S.L.: 1A, 1B, 2A, 2B, 2C, 3B
Financial disclosures of all authors (for the preceding 12 months)
C.G.G. reports funding to Rush University Medical Center from the National Institutes
of Health, Department of Defense, and Michael J. Fox Foundation for research conducted
by Dr. Goetz. During the reporting time, Dr. Goetz directed the Rush Parkinson's Disease
Research Center supported by the Parkinson's Foundation and some of these funds supported
Dr. Goetz's salary as well as his research efforts. He also reports a presidential
stipend from the International Parkinson and Movement Disorder Society paid to Rush
University Medical Center as part of Dr. Goetz's salary, faculty stipends from the
International Parkinson and Movement Disorder Society and the American Academy of
Neurology, and guest professorship honorarium provided by NorthShore University Health
System. C.G.G. reports royalties from Oxford University Press and Wolters Kluwer Publishers
and a salary from Rush University Medical Center. G.T.S. reports consulting and advisory
board membership with 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 the Sunshine
Care Foundation; grants and research from the National Institutes of Health, 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; and honoraria from the International Parkinson and Movement Disorder
Society, American Academy of Neurology, Michael J. Fox Foundation for Parkinson's
Research, US Food and Drug Administration, National Institutes of Health, and Alzheimer's
Association; and a salary from Rush University Medical Center. S.L. reports funding
to Duke University from the National Institutes of Health for research conducted by
Dr. Luo and a salary from Duke University.