When patients go to the hospital for checkups, they usually need to have their blood drawn for laboratory tests to help diagnose the cause of anemia. In fact, this worry is not necessary, because the blood collection tubes used in the clinic nowadays have a volume of 2ml-3ml, and some items may require 3ml-3.5ml of blood collection. Therefore, patients with anemia can safely undergo hematology tests. If you want to clarify the cause of anemia, you may have to undergo more laboratory tests, such as routine blood tests, reticulocytes, peripheral blood smear, biochemical bilirubin, urine routine, blood sample matching, and if abnormal cells or malignant proliferating cells are found in the peripheral blood smear, bone marrow blood will be taken for bone marrow tests.