It is best to register with the hematology department for routine blood tests, because hematology is the specialized department for diagnosing and treating various blood system diseases, no matter what kind of blood system diseases, the most routine test is to do routine blood tests. For example, a routine blood test reveals that the peripheral blood has a reduced trilineage and normal red blood cell pattern and volume, which is often caused by aplastic anemia and can be diagnosed through bone marrow biopsy. If a routine blood test reveals an abnormally high white blood cell count, along with anemia and thrombocytopenia, and if the increased white blood cells are mainly lymphocytes, then acute lymphoblastic leukemia or chronic lymphocytic leukemia should be considered. The diagnosis can be confirmed by bone marrow aspiration, so routine blood tests should be done at the hematology department.