Abstract
OBJECTIVE: To determine the construct validity, test-retest reliability, and measurement error of the shuttle walk test (SWT) for patients after stroke. DESIGN: Clinimetric study. SETTING: Three rehabilitation centers in the Netherlands. PARTICIPANTS: A sample of patients after stroke (N=75; mean age +/- SD, 58.8+/-9.8y) who are capable of walking without physical assistance. Patients were excluded if they had sustained a subarachnoid hemorrhage or a stroke in the cerebellum or brainstem, or had any other conditions that limited their walking capacity more than the current stroke, or had sensory aphasia. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Construct validity (6-minute walk test [6MWT]) and test-retest reliability of the SWT were assessed. Measurement error was determined with the standard error of measurement (SEM), limits of agreement, and smallest detectable differences (SDDs). RESULTS: Construct validity was confirmed by high significant correlations (r(p)>/=.65, P<.01) between the SWT and 6MWT. Difference scores were significantly higher in favor of the SWT for high-speed walkers (>/=0.8m/s). In the small group (n=12) of low-speed walkers (<0.8m/s), no significant correlations and differences between both tests were found except for walking distance in favor of the 6MWT. Test-retest reliability was good (intraclass correlation coefficient model 2,1 [ICC(2,1)]=.961 [.936-.977]). SEM was 6.0%, and the SDDs for individual and group were 302.0m (37%) and 38.7m (5%), respectively. CONCLUSIONS: The SWT is a valid and reliable measure and therefore a feasible instrument to determine functional walking capacity of patients after stroke, especially in high-speed walkers.
