ABSTRACT COMPARISON OF D-DIMER LEVELS IN COVID-19 PATIENTS BASED ON THE SEVERITY OF THE DISEASE AT ARIFIN ACHMAD HOSPITAL, RIAU PROVINCE, JANUARY – DECEMBER 2021 By Thania Nabila Puteri Corona Virus Disease-2019 is a new infectious disease caused by SARS-CoV-2 and attacks the human respiratory system. D-dimer is a protein derived from the degradation of fibrin by plasmin formed by the…