A multiple regression analysis showed that none of the independent variables were important for predicting PIVKA-II or u-OC status (independent variables in the regression model: age, Z-score for body weight and height, FEV1, albumin concentration, vitamin K dose mg/week, diabetes, liver disease, pancreatic insufficiency, Pseudomonas aeruginosa colonization, inhaled and oral permanent antibiotic therapy, intravenous and oral antibiotic therapy in the preceding three months, inhaled glucocorticoid therapy, CFTR mutation). The gene discussed is CFTR; the disease is diabetes mellitus.