Reliability and Minimal Detectable Change of the 2-minute Step Test in Assessing Cardiorespiratory Function Post-COVID-19

Introduction: This study aims to assess the reliability and Minimal Detectable Change (MDC) scores of the 2-Minute Step Test (2MST) for evaluating cardiorespiratory function and to compare its outcomes with those of the 6-Minute Walk Test (6MWT) in post-COVID-19 individuals. Methods: A total of 44 post-COVID-19 individuals participated in the study. Assessments of cardiorespiratory response parameters were conducted using the 2MST and 6MWT on two separate occasions, with a 5-day interval between sessions. Results: Test-retest reliability between the initial and follow-up measurements was excellent for both the 2MST and the 6MWT. The Intraclass Correlation Coefficient (ICC) for the 2MST was 0.92, with MDC95 of 2.92%. Similarly, the ICC for the 6MWT was 0.95, with an MDC95 at 2.56%. Conclusion: The 2MST is a reliable and valid method for assessing exercise tolerance in individuals recovering from COVID-19 and is suitable for use in clinical settings to monitor significant patient improvements.