This algorithm must be integrated into the patient’s own clinical situation, taking into account several considerations such as indications for DOAC treatment; concomitant risk factors and diseases, particularly chronic kidney/liver disease and diabetes; laboratory data (Hb, Ht, creatinine, Cockroft–Gault creatinine clearance, eGFR, AST, ALT, etc.); concomitant drugs; and so on. This evidence concerns the gene GPT and diabetes mellitus.