Reproducibility of Cadence-Free 6-Minute Step Test in Subjects with COPD

Abstract

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 intrarater 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. RE-SULTS: 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.

Prediction of Cardiorespiratory Fitness by the Six-Minute Step Test and Its Association with Muscle Strength and Power in Sedentary Obese and Lean Young Women: A Cross-Sectional Study

“…According to the averaged-single measures ICC analysis (0.97; 95%CI: 0.898–0.993; p<0.001), NSC in the 6MST was reproducible, as previously demonstrated in other populations [ 12 , 13 ].…”

“…However, because of its high technical and cost requirements, indirect protocols for peak oxygen consumption (VO 2peak ) prediction have been developed to minimize these barriers in clinical settings [ 5 – 11 ]. Among the most common functional test protocols, the step test stands out for its low cost, simplicity, portability and accessibility [ 12 – 15 ].…”

Simple Lower Limb Functional Tests in Patients With Chronic Obstructive Pulmonary Disease: A Systematic Review

“…Poor -Costa et al 44 6MST -Fair -Pessoa et al 49 6MST 45 Karloh et al 46 CST II Poor --Perrault et al 48 Step test -Fair -Starobin et al 54 15 …”

“…Puhan et al described the 1-minute STS test as a stronger predictor of 2-year death; a higher number of movements was observed at baseline in those patients who would survive in comparison to non-survivors (19.5 versus 11.8 repetitions; AUC=0.78 of ROC curve) 38 . On the other hand, van Gestel et al, concluded that although the 1-minute STS was associated with objectively measured physical activity, it cannot be used to identify patients with an inactive lifestyle (AUC=0.31) 42 .Step test: A wide variety of protocols concerning the step test have been described in fifteen studies9,10,22,[44][45][46][47][48][49][50][51][52][53][54][55] . There is no standardization regarding cadence (self-paced or externally paced), step height, test duration and how the results should be presented 284(Table 1).…”

Exercise Capacity Impairment Can Predict Postoperative Pulmonary Complications after Liver Transplantation

“…Step tests are widely employed to measure exercise capacity, and their use in the assessment of patients with chronic respiratory conditions is well established [32] . However, it has never been used in patients with ESLD.…”