Reliability of spatiotemporal gait outcome measures in Huntington's disease

Authors

  • Ashwini K. Rao EdD, OTR,

    Corresponding author
    1. Program in Physical Therapy, Department of Rehabilitation Medicine, Columbia University Medical Center, New York, New York, USA
    • Room 812, Neurological Institute, 710 West 168th Street, New York, NY 10032
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  • Lori Quinn EdD, PT,

    1. Program in Physical Therapy, New York Medical College, Valhalla, New York, USA
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  • Karen S. Marder MD, MPH

    1. Departments of Neurology and Psychiatry, Columbia University Medical Center, New York, New York, USA
    2. G. H. Sergievsky Center, Taub Institute for Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, New York, USA
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Abstract

Gait impairments are very important in Huntington's disease (HD), because loss of independence in gait is an important predictor of nursing home placement. Given this importance, it is imperative to test reliable and sensitive outcome measures that can be tested easily in various clinical environments. Here, we examined the test–retest reliability of gait outcome measures using the GAITRite instrumented carpet. We tested 12 subjects with HD and 12 age-matched controls in two separate sessions. At each session, subjects walked across the GAITRite carpet at a comfortable speed. We used the intraclass correlation coefficient (ICC) and coefficient of variation (CoV) to measure test–retest reliability. Reliability was very high for all outcome measures (velocity, cycle time, stride length, cadence, and base of support), as seen by high ICC scores (0.86 to 0.95) and low CoV scores (0.042–0.102). In addition, the performance across the two subject groups was very different, indicating that the GAITRite is sensitive enough to distinguish between populations. Given that the GAITRite is a relatively inexpensive and portable piece of equipment, it can be used in a wide variety of clinical settings and clinical trials. Our data on high test–retest reliability and sensitivity extends the utility of the GAITRite to the HD population. © 2005 Movement Disorder Society

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