Validation and prognostic value of the five-repetition sit-to-stand test in patients with severe exacerbation of COPD.
BACKGROUND A severe exacerbation of COPD (ECOPD) may negatively impact patients' functioning; however, there is a lack of validated, simple, and low-cost tools to assess physical function in this setting. Thus, the aims of this study were to explore the construct validity of the five-repetition sit-to-stand (5STS) test...