The Bionics Institute, East Melbourne, Australia; Department of Medical Bionics, University of Melbourne, Australia.
The Bionics Institute, East Melbourne, Australia.
J Neurosci Methods. 2019 Jan 1;311:377-384. doi: 10.1016/j.jneumeth.2018.09.022. Epub 2018 Sep 19.
Tremor is a debilitating symptom of Multiple Sclerosis (MS). Little is known about its pathophysiology and treatments are limited. Clinical trials investigating new interventions often rely on subjective clinical rating scales to provide supporting evidence of efficacy.
We present a novel instrument (TREMBAL) which uses electromagnetic motion capture technology to quantify MS tremor. We aim to validate TREMBAL by comparison to clinical ratings using regression modelling with 310 samples of tremor captured from 13 MS participants who performed five different hand exercises during several follow-up visits. Minimum detectable change (MDC) and test-retest reliability were calculated and comparisons were made between MS tremor and data from 12 healthy volunteers.
Velocity of the index finger was most congruent with clinical observation. Regression modelling combining different features, sensor configurations, and labelling exercises did not improve results. TREMBAL MDC was 84% of its initial measurement compared to 91% for the clinical rating. Intra-class correlations for test-retest reliability were 0.781 for TREMBAL and 0.703 for clinical ratings. Tremor was lower (p = 0.002) in healthy subjects.
Subjective scales have low sensitivity, suffer from ceiling effects, and mitigation against inter-rater variability is challenging. Inertial sensors are ubiquitous, however, their output is nonlinearly related to tremor frequency, compensation is required for gravitational artefacts, and their raw data cannot be intuitively comprehended.
TREMBAL, compared with clinical ratings, gave measures in agreement with clinical observation, had marginally lower MDC, and similar test-retest reliability.
震颤是多发性硬化症（MS）的一种致残症状。其病理生理学知之甚少，治疗方法也有限。研究新干预措施的临床试验通常依赖于主观临床评分量表来提供疗效的支持证据。
我们提出了一种新的仪器（TREMBAL），该仪器使用电磁运动捕捉技术来量化 MS 震颤。我们旨在通过比较 13 名 MS 参与者在多次随访期间进行的五项不同手部运动的 310 个震颤样本的回归模型，用 TREMBAL 与临床评分进行验证。计算了最小可检测变化（MDC）和测试-重测可靠性，并对 MS 震颤数据与 12 名健康志愿者的数据进行了比较。
食指速度与临床观察最一致。结合不同特征、传感器配置和标记练习的回归模型并不能提高结果。与临床评分相比，TREMBAL 的 MDC 为其初始测量值的 84%，为 91%。TREMBAL 和临床评分的测试-重测可靠性的组内相关系数分别为 0.781 和 0.703。健康受试者的震颤幅度较低（p=0.002）。
主观量表的灵敏度低，存在天花板效应，且难以缓解评分者间的变异性。惯性传感器无处不在，但其输出与震颤频率呈非线性关系，需要对重力伪影进行补偿，并且其原始数据无法直观理解。
与临床评分相比，TREMBAL 的测量值与临床观察一致，MDC 略低，测试-重测可靠性相似。
