Haematology is concerned with the blood, bone marrow, lymph nodes and their diseases. Blood diseases can be the consequence of diseases of the haematopoietic (blood-forming) tissue, the bone marrow or a direct disease of the blood cell. Blood diseases include coagulation problems, anaemia and cancers (leukaemia, lymphomas, multiple myelomas), among others. Laboratory tests of blood samples to examine the composition of the blood and the blood cells as well as blood coagulation factors are among the subsectors of haematology.