쿤밍 의대 제2병원의 만성폐쇄성폐질환 글로벌 이니셔티브(Global Initiative for 만성폐질환 진단기준)를 충족한 350명의 환자가 처음에 이 연구에 포함되었다.
Three hundred and fifty patients who met the Global Initiative for Chronic Obstructive Lung Disease diagnostic criteria of COPD from The Second Affiliated Hospital of Kunming Medical University were initially included in the study.