A hemoglobin test is used to determine levels of haemoglobin in your blood. hemoglobin, is a protein found in RBC that transfers oxygen from your lungs to the rest of your body. A blood disorder could be indicated if your haemoglobin levels are abnormal. Anemia is a disorder in which your body has less red blood cells than normal. This test is commonly performed to check for anaemia. Anaemia is a condition in which your RBC don’t get enough oxygen