Room for methodological improvement in gait speed study for COPD patients.

We have read with great interest the article by Walsh et al ., who investigated whether slower gait speed is an independent risk factor for readmission and mortality in patients hospitalised with chronic obstructive pulmonary disease (COPD) exacerbation [1]. This study included 213 patients hospitalised with COPD exacerbation. The Cox proportional hazards model and the Fine and Grey model revealed that four-meter gait speed (4MGS) within 24 h before hospital discharge was associated with both readmission and mortality within 12 months. Considering that 4MGS is a simple and potentially ameliorable measurement, 4MGS could be an important predictor; however, there are some concerns regarding the methodology of this study. Footnotes This manuscript has recently been accepted for publication in the European Respiratory Journal . It is published here in its accepted form prior to copyediting and typesetting by our production team. After these production processes are complete and the authors have approved the resulting proofs, the article will move to the latest issue of the ERJ online. Please open or download the PDF to view this article.