Session Information
Date: Wednesday, June 22, 2016
Session Title: Ataxia
Session Time: 12:00pm-1:30pm
Location: Exhibit Hall located in Hall B, Level 2
Objective: To determine the reliability and discriminant validity of the Scale for Assessment and Rating of Ataxia (SARA) in early onset ataxia.
Background: Early onset ataxia (EOA) involves heterogeneous disorders regarding age-of-onset (0-25 years), pathogenesis and presentation. The Scale for Assessment and Rating of Ataxia (SARA) is uniformly interpreted in children and adults. Innovative therapeutic trials are applying SARA-scores in children and adults, using minimal quantitative cut-off points, suggesting that any smallest SARA-score difference would reflect therapeutic “ataxia” improvement. However, pediatric SARA-scores have shown to be influenced by age and muscle weakness as well. In the present EOA study, we therefore aimed to determine the influence by phenotypic heterogeneity on SARA-scores.
Methods: In 38 EOA patients [mean age 15 (range 5-34) years], we determined inter-observer agreement and discriminant validity of SARA-scores (by 3 independent pediatric neurologists) in “primary” (ataxia as primary movement disorder (n =26)) and “combined” (ataxia concurring with another prevailing movement disorder (n=12)) subgroups.
Results: The Interclass Correlation Coefficient revealed high, but not complete, inter-observer agreement in “primary” and “combined” EOA-subgroups (.977 and .891). In both subgroups the SARA-scores were predicted by the severity of the primary movement disorder, instead of by ataxia alone (β .83; p <.05) .
Conclusions: In EOA, SARA-scores are not infallibly reproducible, implicating that the smallest SARA cut off may refer to the margin of error. In heterogeneous EOA-subgroups, discriminant validity between the influence by ataxia and other concurrent movement disorders is low, implicating that decreased SARA-scores in combined EOA patients do not necessarily reflect “ataxia” improvement. To prevent over-interpretation of SARA-scores, insight in the SARA construct is needed first.
These data have been (partly) presented at the EPNS congres 2015 in Vienna on May 29th 2015 and at the 19th International Congres of Parkinson’s disease and Movement Disorders in San Diego on June 17th 2015.
To cite this abstract in AMA style:
R. Brandsma, T.F. Lawerman, M.J. Kuiper, I.J. Lunsing, H. Burger, D.A. Sival. The scale for assessment and rating of ataxia in early onset ataxia; always a reliable biomarker? [abstract]. Mov Disord. 2016; 31 (suppl 2). https://www.mdsabstracts.org/abstract/the-scale-for-assessment-and-rating-of-ataxia-in-early-onset-ataxia-always-a-reliable-biomarker/. Accessed June 14, 2025.« Back to 2016 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/the-scale-for-assessment-and-rating-of-ataxia-in-early-onset-ataxia-always-a-reliable-biomarker/