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Test-retest reliability of the Friedreich's ataxia rating scale
Christian Rummey1, Theresa A Zesiewicz2, Santiago Perez-Lloret3,4
1Clinical Data Science GmbH, Basel, Switzerland.
Abstract:
The modified Friedreich Ataxia Rating Scale (mFARS) is a disease specific, exam-based neurological rating scale commonly used as a outcome measure in clinical trials. While extensive clinimetric testing indicates it's validity in measuring disease progression, formal test-retest reliability was lacking. To fill this gap, we acquired results from screening and baseline visits of several large clinical trials and calculated intraclass correlation coefficients, coefficients of variance, standard error, and the minimally detectable changes. This study demonstrated excellent test-retest reliability of the mFARS, and it's upright stability subscore.
Insights
The modified Friedreich Ataxia Rating Scale (mFARS) shows excellent test-retest reliability for measuring Friedreich
Area of Science:
- Neurology
- Clinical Trials
- Biostatistics
Background:
- The modified Friedreich Ataxia Rating Scale (mFARS) is a key outcome measure in Friedreich's Ataxia clinical trials.
- While mFARS validity is established, its test-retest reliability needed formal assessment.
Purpose of the Study:
- To formally evaluate the test-retest reliability of the mFARS scale.
- To assess the reliability of the mFARS upright stability subscore.
Main Methods:
- Utilized data from screening and baseline visits of multiple Friedreich's Ataxia clinical trials.
- Calculated intraclass correlation coefficients (ICCs), coefficients of variance (CV), standard error of measurement (SEM), and minimally detectable change (MDC).
Main Results:
- Demonstrated excellent test-retest reliability for the overall mFARS.
- Confirmed excellent test-retest reliability for the mFARS upright stability subscore.
Conclusions:
- The mFARS is a reliable tool for assessing disease progression in Friedreich's Ataxia clinical trials.
- The findings support the continued use of mFARS in clinical research for this condition.
