Abnormal findings also included elevated d-dimer, fibrinogen degradation products (FDP), increased prothrombin time (PT), activated partial thromboplastin time (APTT), international normalized ratio (INR), and decreased prothrombin time activity (PTA) compared to healthy donors, non-COVID-19 patients, or COVID-19 patients with mild symptoms only. Here, F2 is linked to COVID-19.