Missing data were present in the following variables: BMI, CRP, albumin, alanine aminotransferase, blood urea nitrogen, total cholesterol, triglyceride, creatinine, education status, PIR, smoking, hypertension, asthma, arthritis, emphysema, chronic bronchitis, liver disease, cancer, CHF, CHD, AP, HT, and stroke. The gene discussed is ALB; the disease is chronic bronchitis.