According to the World Health Organization, anemia is diagnosed according to the hemoglobin level in the body. The hemoglobin level is usually included in the routine blood test, which can be done by drawing venous blood or finger blood. The diagnosis of anemia is confirmed. Hemoglobin is the main component of red blood cells and is composed of iron ions and pearl protein. The human body is rich in protein but limited in iron, so if you are anemic, you should further check iron quadruple or iron triple to confirm the diagnosis of iron deficiency anemia.