Screening high-risk cases of COPD combined with lung cancer

Clinical data including age, smoking index(number of cigarettes smoked per day×number of years smoking), body mass index (BMI), duration of chronic cough and sputum, pulmonary nodules, emphysema, whether or not they quit smoking, and peripheral blood leukocyte count, monocyte count, monocyte percentage, neutrophil count, neutrophil percentage, lymphocyte count, lymphocyte percentage, and platelet count, mean platelet volume, mean red blood cell volume, fibrinogen, cholesterol, bilirubin, NLR, PLR.