Erythrocyte osmotic fragility test. High, mainly seen in hereditary spherocytosis, autoimmune hemolytic anemia, congenital hemolytic jaundice. Decrease, mainly suggested in sickle cell anemia, obstructive jaundice, iron deficiency anemia, thalassemia, lead poisoning, pernicious anemia, post-splenectomy liver disease, etc. To check the erythrocyte fragility test, the people who need to be examined mainly include patients with anemia, lead poisoning, jaundice, and liver abnormalities. During the examination, the osmotic fragility test of thalassemia will be reduced, and a low concentration of sodium chloride solution should be performed. Blood specimens should not be stored in the refrigerator for more than 6 hours.