RT Journal Article
SR Electronic
T1 Reproducibility of Cadence-Free 6-Minute Step Test in Subjects with COPD
JF Respiratory Care
FD American Association for Respiratory Care
SP 538
OP 542
DO 10.4187/respcare.02743
VO 59
IS 4
A1 Joyce NF da Costa
A1 Juliano F Arcuri
A1 Ivana L Gonçalves
A1 Simone F Davi
A1 Bruna V Pessoa
A1 Mauricio Jamami
A1 Valéria AP Di Lorenzo
YR 2014
UL http://rc.rcjournal.com/content/59/4/538.abstract
AB BACKGROUND: Six-minute step test (6MST) has been used to assess functional capacity in chronic conditions; however, its reproducibility in the COPD population has not been evaluated. Our study objective was to evaluate 6MST reproducibility. METHODS: The test was performed in a single 20-cm height step, and subjects were instructed to step up and down (cadence-free) for 6 min. Subjects underwent three tests. The first and second were controlled by the same assessor with a 30-min interval. The third test was controlled by a different assessor one week later. For intra-rater comparison, the first and second performances of the test were used, and for inter-assessor comparison, the better performance of the first two tests was compared with the third test. RESULTS: Excellent intra-rater and inter-rater relative reproducibility was observed (intraclass correlation coefficient > 0.8), and there was no statistical difference (repeated measures of analysis of variance) among the performances of the three tests. Intra-rater error values were acceptable (mean error of 5.7 steps and limits of agreement between −7 and 18 steps). Inter-rater error values were not acceptable (mean error of 4.4 steps and limits of agreement between −20 and 29 steps. CONCLUSIONS: 6MST proved to be reproducible in the COPD population when performed by the same assessor.