A change in single-leg-stance-time (SLST) performance in older adults should exceed 24.1 seconds in order to be considered real change, say authors of an article published in the April issue of Gait & Posture. SLST exhibits poor absolute reliability, the authors add, and appears unlikely to be sensitive to detecting change in performance in geriatric clinical settings and research studies.
A measure of absolute reliability, the standard error of measurement (SEM), can be used to compute minimal detectable change (MDC), a clinically useful indicator of change in performance exceeding that attributable to measurement error. The purpose of this study was to quantify MDC for SLST in community-dwelling older adults.
Twenty-five adults (60-89 years) performed repeated trials of SLST. Relative and absolute reliability for SLST were quantified using the intraclass correlation coefficient and SEM. The MDC was computed from the SEM.
SEM was 8.7s and MDC at the 95% confidence level was 24.1 seconds for SLST. SLST exhibited large measurement error (40.8%) and high minimum change (113.1%) percent values.