Study design and oversight
ACUTE EXACERBATION OF COPD, DISEASES
G * Power was used to estimate the sample size, effect size This clinical trial was an open‐label non‐randomized clinical trial that enrolled patients with acute exacerbation of COPD in the Department of Respiratory and Critical Diseases at the Central Hospital Affiliated to Shenyang Medical College between September 13, 2019, and July 31, 2020. The final follow‐up ended on January 31, 2021. The study comprised a 1‐week drug adaptation period followed by a treatment phase. The patients were divided into two groups (doxofylline group [DG]: This study was conducted in line with the Helsinki Statement and approved by the Ethics Committee of Shenyang Medical College Hospital. All patients provided written informed consent before undertaking the study.