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.