Kondo Y1, Bando K1, Ariake Y1, Katsuta W1, Todoroki K1, Takahashi Y2
1National Center of Neurology and Psychiatry, Rehabilitation, Kodaira, Japan, 2National Center of Neurology and Psychiatry, Neurology, Kodaira, Japan
Background: Spinocerebellar degeneration (SCD) presents balance disorder as a cardinal symptom. Balance impediment is assessed using the Balance Evaluation Systems Test (BESTest), comprising six categories. BESTest and its two abbreviated versions, Mini-Balance Evaluation Systems Test (Mini-BESTest) and Brief-Balance Evaluation Systems Test (Brief-BESTest), have been validated in elderly and patients with Parkinson's disease. However, these tests have not been validated in patients with SCD.
Purpose: This study aimed to determine the test-retest reliability and minimal detectable change (MDC) of BESTest, Mini-BESTest, and Brief-BESTest in patients with SCD.
Methods: Twenty patients [mean age: 63.6 ± 9.8, 13 males] with SCD with an established genetic diagnosis and a gait score of 5 on the Scale for the Assessment and Rating of Ataxia were enrolled in this study. Four patients had Machado-Joseph disease/spinocerebellar ataxia (SCA) 3, nine had SCA6, and seven had SCA31. Patients underwent BESTest at baseline and again after 1 month. Mini-BESTest and Brief-BESTest scores were extracted based on BESTest scores. Interclass correlation coefficient (ICC: 1,1) was used as a measure of relative reliability. MDC at the 95% confidence level (MDC95) was calculated for all tests after confirming systematic error using Bland-Altman analysis. All procedures were approved by the institutional review board.
Results: BESTest, Mini-BESTest, and Brief-BESTest exhibited high test-retest reliability (ICC: 0.81-0.92). Bland-Altman plot revealed no systematic errors. MDC95 values were 8.7, 4.1, and 5.2 points for BESTest, Mini-BESTest, and Brief-BESTest, respectively.
Conclusion(s): BESTest and its short versions demonstrated high test-retest reliability. Values less than 8.7, 4.1, and 5.2 points for BESTest, Mini-BESTest, and Brief-BESTest were considered acceptable errors of measurement regarding MDC.
Implications: These findings suggest that a clinically significant difference in balance must be greater than the respective aforementioned values.
Keywords: Spinocerebellar degeneration, BESTest, Minimal Detectable Change
Funding acknowledgements: We gratefully acknowledge the work of past and present members of our laboratory and participants.
Purpose: This study aimed to determine the test-retest reliability and minimal detectable change (MDC) of BESTest, Mini-BESTest, and Brief-BESTest in patients with SCD.
Methods: Twenty patients [mean age: 63.6 ± 9.8, 13 males] with SCD with an established genetic diagnosis and a gait score of 5 on the Scale for the Assessment and Rating of Ataxia were enrolled in this study. Four patients had Machado-Joseph disease/spinocerebellar ataxia (SCA) 3, nine had SCA6, and seven had SCA31. Patients underwent BESTest at baseline and again after 1 month. Mini-BESTest and Brief-BESTest scores were extracted based on BESTest scores. Interclass correlation coefficient (ICC: 1,1) was used as a measure of relative reliability. MDC at the 95% confidence level (MDC95) was calculated for all tests after confirming systematic error using Bland-Altman analysis. All procedures were approved by the institutional review board.
Results: BESTest, Mini-BESTest, and Brief-BESTest exhibited high test-retest reliability (ICC: 0.81-0.92). Bland-Altman plot revealed no systematic errors. MDC95 values were 8.7, 4.1, and 5.2 points for BESTest, Mini-BESTest, and Brief-BESTest, respectively.
Conclusion(s): BESTest and its short versions demonstrated high test-retest reliability. Values less than 8.7, 4.1, and 5.2 points for BESTest, Mini-BESTest, and Brief-BESTest were considered acceptable errors of measurement regarding MDC.
Implications: These findings suggest that a clinically significant difference in balance must be greater than the respective aforementioned values.
Keywords: Spinocerebellar degeneration, BESTest, Minimal Detectable Change
Funding acknowledgements: We gratefully acknowledge the work of past and present members of our laboratory and participants.
Topic: Outcome measurement
Ethics approval required: Yes
Institution: National Center of Neurology and Psychiatry
Ethics committee: National Center of Neurology and Psychiatry
Ethics number: A2016-064
All authors, affiliations and abstracts have been published as submitted.
