Impact of Course Configuration on 6-Minute Walk Test Performance of People with Lower Extremity Amputations

Abstract

Purpose: The configuration of the 6-minute walk test (6MWT) may influence the distance walked and comparability of results among subjects and across programmes. The purpose of this study was to evaluate the relative and absolute test-retest reliability of two 6MWT configurations and to evaluate the agreement between these two configurations in users of lower extremity prosthetics. Methods: A cross-sectional design was used to analyze data from 25 subjects completing in-patient prosthetic rehabilitation (mean age 63.12 [SD 13.77] y; 72% male). Two configurations of the 6MWT were examined, and relative and absolute test-retest reliabilities were calculated. Bland-Altman plots were constructed to evaluate agreement between configurations. Results: The relative test-retest reliability was excellent for both Configuration 1 and Configuration 2: ICC 0.97, 95% CI: 0.93, 0.98, and ICC 0.97, 95% CI: 0.94, 0.99, respectively. Comparable values for absolute test-retest reliability were also found. The Bland-Altman plot demonstrated a difference of ±63.92 meters between configurations. Conclusions: The two 6MWT configurations had excellent relative and absolute test-retest reliability, but the results from each configuration do not agree sufficiently to make them interchangeable or directly comparable. This highlights the importance of explicitly indicating the test configuration for the 6MWT when reporting results.

Keywords: amputees; exercise test; lower extremity; prostheses.

Figures

Figure 1

Bland–Altman plot for Configurations 1 and 2 of the 6-minute walk test.