Development of a PLS-Specific Clinical Rating Scale, Capable of Evaluating the Clinical Functional State of Patients with PLS in Multi-Site Study


About this study

The purpose of this study is to assess the internal consistency and construct validity of the scale, assess test-retest reliability, intra-rater reliability, inter-rater reliability, reliability between in-person and telephone administration of the scale, to determine the sensitivity of the scale to detect changes over time.

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Inclusion criteria:

  • ≥ 20 years of age
  • Pure UMN dysfunction (spasticity, pathological hyperreflexia, pathological reflexes with or without motor weakness) of undetermined etiology in at least both the arms and legs (to clinically exclude hereditary spastic paraplegia, HSP)
  • Symptom onset (defined as subjective weakness or stiffness of the skeletal or bulbar muscles) less than 15 years prior to the baseline visit, exactly as in our current PLS COSMOS study
  • Negative test result for HSP or HSP-related mutation (if a molecular diagnostic test for HSP was done
  • Normal nerve conduction studies and normal needle electrode EMG examination when the diagnosis of PLS was made
  • Expected to have at least some bulbar symptoms (dysarthria, dysphagia, drooling or pseudobulbar affect), but the absence of these symptoms will not exclude the patient when all other inclusion criteria have been met 
  • Normal neuroimaging except for changes expected for PLS
  • No active major neurological diseases other than PLS and no history of major neurological diseases
  • No major unstable medical diseases that require treatment (i.e. active cancer, dialysis) in the past 6 months

Exclusion criteria:

  • UMN symptoms and signs only in the legs.
  • Residing outside of commutable distance and unwilling to visit the study site as required
  • Unwilling to give informed consent.


Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status

Jacksonville, Fla.

Mayo Clinic principal investigator

Eric Sorenson, M.D.

Closed for enrollment

Rochester, Minn.

Mayo Clinic principal investigator

Eric Sorenson, M.D.

Closed for enrollment

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