The different types of Hematology may include the following. Haemoglobinopathy is the study of hemoglobin deficiency in the blood. Hematological malignancy is concerned with the diagnosis and treatment of blood cancers. Anaemia is the study of lowered hemoglobin or red blood cells. Coagulopathy is the study of bleeding abnormalities which signifies how well the body is able to form blood clots.