Validity of balance measures in cerebellar ataxia: A prospective study with 12-month follow-up

Abstract

Introduction: Balance deficits are common in cerebellar ataxia. Determining which balance outcome measures are psychometrically strong for this population remains an unmet need. Objective: To evaluate the validity and responsiveness of two clinic-based balance measures (Berg Balance Scale [BBS] and balance sub-component of the Scale for the Assessment and Rating of Ataxia [SARA-bal]) and two laboratory-based balance measures (Sensory Organization Test [SOT] and Limits of Stability [LOS]) in cerebellar ataxia. Design: Prospective cohort study. Setting: Institutional study assessing 40 participants with cerebellar ataxia at baseline, and 6 and 12 months. Main outcome measures: Balance was assessed using the BBS, SARA-bal, SOT, and LOS; disease severity was assessed using the SARA; and Patients' Global Impression of Change (PGIC) was used to estimate responsiveness to disease progress at 6 and 12 months. Results: BBS and SARA-bal (Spearman's correlation coefficient, ρS = −0.89, p