Clinimetric Properties of the Fragile X-associated Tremor Ataxia Syndrome Rating Scale

Deborah A Hall; Glenn T Stebbins; Sebastien Jacquemont; Elizabeth Berry-Kravis; Christopher G Goetz; Randi Hagerman; Lin Zhang; Maureen A Leehey

doi:10.1002/mdc3.12708

Clinimetric Properties of the Fragile X-associated Tremor Ataxia Syndrome Rating Scale

Mov Disord Clin Pract. 2019 Jan 22;6(2):120-124. doi: 10.1002/mdc3.12708. eCollection 2019 Feb.

Authors

Deborah A Hall¹, Glenn T Stebbins¹, Sebastien Jacquemont², Elizabeth Berry-Kravis^{1

3}, Christopher G Goetz¹, Randi Hagerman⁴, Lin Zhang⁵, Maureen A Leehey⁶

Affiliations

¹ Department of Neurological Sciences and Pediatrics Rush University Chicago Illinois United States.
² Department of Pediatrics University of Montreal Montreal Canada.
³ Department of Pediatrics Rush University Chicago Illinois United States.
⁴ MIND Institute and Department of Pediatrics University of California Davis School of Medicine Sacramento CA United States.
⁵ Department of Neurology University of California Davis School of Medicine Sacramento CA United States.
⁶ Department of Neurology University of Colorado School of Medicine Aurora Colorado United States.

Abstract

Background: There are currently no proven treatments for fragile X-associated tremor and ataxia syndrome (FXTAS). Validated outcome measures are needed in order to plan and conduct clinical trials to aid in the development of therapy.

Methods: This study examined the reliability and construct validity of the FXTAS Rating Scale. The study was conducted by using ratings from movement disorder specialists, who were blinded to gene status, on the FXTAS Rating Scale.

Results: In 295 premutation carriers with and without FXTAS, 33 scale items showed a high level of overall reliability, adequate item-to-total correlations and construct validity. Factor analysis revealed four components.

Conclusions: The result demonstrates that many items in the scale meet standard clinimetric criteria, but modification of the scale improved the overall utility.

Keywords: FMR1; FXTAS Rating Scale; Fragile X‐associated tremor ataxia syndrome.