Functional Disability Score
The functional disability score (FDS) is a clinical scale that has been
developed and previously validated9 to analyze the
clinical disability in patients with PLP1-related disorders. The
clinical scale measures the ability of patients to perform routine tasks
of daily living. The scoring system does not depend on any one
neurologic sign but is a reproducible scale that can collate responses
from a patient’s caregiver. The inter-rater reliability of the scoring
system is greater than 95% among a small team of neurologists at Wayne
State University School of Medicine who estimated the functional
disability of a group of 20 patients with genetically confirmed
PMD.9 The FDS of this cohort of patients was
determined by either direct examination of the patient, interview with
the caregiver of the patient, and/or written report of the caregiver.