Reliability of COP-based postural sway measures.
Lin-D; Seol-H; Nussbaum-MA; Madigan-ML
Proceedings of the Human Factors and Ergonomics Society 50th Annual Meeting, Oct. 16-20, 2006, San Francisco, California. Santa Monica, CA: Human Factors and Ergonomics Society, 2006 Oct; 50(13):1336-1340
Measures of human sway during upright standing are frequently used as indirect measures of the postural control system. The objective of this study was to assess the reliability of several center-of-pressure-based sway measures. Test-retest reliability was determined both within-days (under different visual and surface conditions) and between-days (5 different days). Intraclass Correlation Coefficient (ICC), Standard Error of Measurement (SEM), Minimal Metrically Detectable Change (MMDC), and Coefficient of Variation (CV) were used as reliability indices. Mean velocity was found to be the most reliable measure among those evaluated. Overall, between-day reliability indices were better than within-day reliability. When subjects were standing on a compliant surface, several measures exhibited better reliability under 'eyes open' condition. These results can be useful in guiding the selection of postural sway measures and appropriate number of replications to improve sway assessment.
Humans; Men; Women; Posture; Musculoskeletal-system; Muscle-function; Muscles; Physical-capacity; Physiological-function; Physiological-measurements; Physiology
Michael L. Madigan, Department of Engineering Science and Mechanics, Virginia Tech, Mail Code 0219, Blacksburg, VA 24061
Proceedings of the Human Factors and Ergonomics Society 50th Annual Meeting, Oct. 16-20, 2006, San Francisco, California
Virginia Polytechnic Institute and State University