Objective: This study was to report the within-day test-retest reliability and the measurement properties of the six-minute walk test (6MWT) in persons with lower-limb (transtibial) amputation.
Design: Test-retest study design.
Setting: University research laboratory.
Participants: Subjects (N=13) with transtibial amputation (9 men and 4 women; mean age, 46 y).
Interventions: Three trials of the 6MWT were conducted within 1 day with 20 to 30 minutes of rest between consecutive trials. Timed Up & Go (TUG) test and timed one-leg balance tests were conducted on another day.
Main outcome measures: (1) Distance, heart rate, symptoms and signs of exercise intolerance during the walk test, (2) times of the TUG test and the one-leg balance test.
Results: The intraclass correlation coefficient (ICC3,1) value was .94. Bland and Altman graphs showed no systemic variations between trials and a small learning effect. The peak heart rate approximated 72% to 78% of the age-predicted maximal heart rate. Moderate degrees of correlation were observed in: (1) the 6MWT versus the TUG test (r=-.76, P<.05), and (2) the 6MWT versus the timed prosthetic-leg stance (with eyes open: r=.63, P<.05; with eyes closed: r=.61, P<.05).
Conclusions: These findings suggest that the 6MWT could be considered as a reliable measure of functional capacity, involves a moderate degree of exercise intensity, and is related in a moderate degree to postural control abilities in persons with transtibial amputation.